77783778671472 has 160 divisors (see below), whose sum is σ = 225627638549760. Its totient is φ = 25655334716160.

The previous prime is 77783778671471. The next prime is 77783778671519. The reversal of 77783778671472 is 27417687738777.

77783778671472 is a `hidden beast` number, since 7 + 7 + 7 + 8 + 3 + 7 + 78 + 6 + 71 + 472 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 77783778671391 and 77783778671400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77783778671471) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13551322 + ... + 18417542.

It is an arithmetic number, because the mean of its divisors is an integer number (1410172740936).

Almost surely, 2^{77783778671472} is an apocalyptic number.

77783778671472 is a gapful number since it is divisible by the number (72) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77783778671472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112813819274880).

77783778671472 is an abundant number, since it is smaller than the sum of its proper divisors (147843859878288).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77783778671472 is a wasteful number, since it uses less digits than its factorization.

77783778671472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4866628 (or 4866616 counting only the distinct ones).

The product of its digits is 7589772288, while the sum is 81.

The spelling of 77783778671472 in words is "seventy-seven trillion, seven hundred eighty-three billion, seven hundred seventy-eight million, six hundred seventy-one thousand, four hundred seventy-two".