77568638820 has 48 divisors (see below), whose sum is σ = 222489566208. Its totient is φ = 20180458240.

The previous prime is 77568638813. The next prime is 77568638839. The reversal of 77568638820 is 2883686577.

It is a super-2 number, since 2×77568638820² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15763524 + ... + 15768443.

It is an arithmetic number, because the mean of its divisors is an integer number (4635199296).

Almost surely, 2^77568638820 is an apocalyptic number.

It is an amenable number.

77568638820 is an abundant number, since it is smaller than the sum of its proper divisors (144920927388).

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

77568638820 is a wasteful number, since it uses less digits than its factorization.

77568638820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31532020 (or 31532018 counting only the distinct ones).

The product of its (nonzero) digits is 27095040, while the sum is 60.

The spelling of 77568638820 in words is "seventy-seven billion, five hundred sixty-eight million, six hundred thirty-eight thousand, eight hundred twenty".