77620155690 has 384 divisors, whose sum is σ = 246616473600. Its totient is φ = 15600816000.

The previous prime is 77620155661. The next prime is 77620155733. The reversal of 77620155690 is 9655102677.

It is a super-2 number, since 2×77620155690² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 38596785 + ... + 38598795.

It is an arithmetic number, because the mean of its divisors is an integer number (642230400).

Almost surely, 2^77620155690 is an apocalyptic number.

77620155690 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 77620155690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123308236800).

77620155690 is an abundant number, since it is smaller than the sum of its proper divisors (168996317910).

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

77620155690 is a wasteful number, since it uses less digits than its factorization.

77620155690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2095 (or 2070 counting only the distinct ones).

The product of its (nonzero) digits is 793800, while the sum is 48.

The spelling of 77620155690 in words is "seventy-seven billion, six hundred twenty million, one hundred fifty-five thousand, six hundred ninety".