78214749561 has 81 divisors (see below), whose sum is σ = 125323909581. Its totient is φ = 46984392000.

The previous prime is 78214749553. The next prime is 78214749643. The reversal of 78214749561 is 16594741287.

The square root of 78214749561 is 279669.

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

78214749561 is a `hidden beast` number, since 7 + 8 + 2 + 1 + 4 + 74 + 9 + 561 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2950119225 + 75264630336 = 54315^2 + 274344^2 .

It is not a de Polignac number, because 78214749561 - 2³ = 78214749553 is a prime.

It is a super-2 number, since 2×78214749561² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78214749498 and 78214749507.

It is not an unprimeable number, because it can be changed into a prime (78214749511) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 774403411 + ... + 774403511.

Almost surely, 2^78214749561 is an apocalyptic number.

78214749561 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

78214749561 is the 279669-th square number.

78214749561 is the 139835-th centered octagonal number.

It is an amenable number.

78214749561 is a deficient number, since it is larger than the sum of its proper divisors (47109160020).

78214749561 is a wasteful number, since it uses less digits than its factorization.

78214749561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 376 (or 188 counting only the distinct ones).

The product of its digits is 3386880, while the sum is 54.

The spelling of 78214749561 in words is "seventy-eight billion, two hundred fourteen million, seven hundred forty-nine thousand, five hundred sixty-one".