47779849816209 has 243 divisors, whose sum is σ = 85033545436827. Its totient is φ = 26767510693056.

The previous prime is 47779849816187. The next prime is 47779849816217. The reversal of 47779849816209 is 90261894897774.

The square root of 47779849816209 is 6912297.

It is a perfect power (a square), and thus also a powerful number.

47779849816209 is a `hidden beast` number, since 4 + 7 + 7 + 7 + 98 + 498 + 16 + 20 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 27122170331025 + 20657679485184 = 5207895^2 + 4545072^2 .

It is a tau number, because it is divible by the number of its divisors (243).

It is not a de Polignac number, because 47779849816209 - 2⁵ = 47779849816177 is a prime.

It is a super-2 number, since 2×47779849816209² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is not an unprimeable number, because it can be changed into a prime (47779849016209) by changing a digit.

It is a polite number, since it can be written in 242 ways as a sum of consecutive naturals, for example, 286106885044 + ... + 286106885210.

Almost surely, 2^{47779849816209} is an apocalyptic number.

47779849816209 is a gapful number since it is divisible by the number (49) formed by its first and last digit.

47779849816209 is the 6912297-th square number.

47779849816209 is the 3456149-th centered octagonal number.

It is an amenable number.

47779849816209 is a deficient number, since it is larger than the sum of its proper divisors (37253695620618).

47779849816209 is an frugal number, since it uses more digits than its factorization.

47779849816209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518 (or 250 counting only the distinct ones).

The product of its (nonzero) digits is 3072577536, while the sum is 81.

47779849816209 divided by its sum of digits (81) gives a square (589874689089 = 768033²).

The spelling of 47779849816209 in words is "forty-seven trillion, seven hundred seventy-nine billion, eight hundred forty-nine million, eight hundred sixteen thousand, two hundred nine".