61977794790 has 64 divisors (see below), whose sum is σ = 155337523200. Its totient is φ = 15796243584.

The previous prime is 61977794737. The next prime is 61977794807. The reversal of 61977794790 is 9749777916.

61977794790 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×61977794790² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 847396 + ... + 917624.

It is an arithmetic number, because the mean of its divisors is an integer number (2427148800).

Almost surely, 2^61977794790 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61977794790, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77668761600).

61977794790 is an abundant number, since it is smaller than the sum of its proper divisors (93359728410).

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

61977794790 is a wasteful number, since it uses less digits than its factorization.

61977794790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71541.

The product of its (nonzero) digits is 42007896, while the sum is 66.

The spelling of 61977794790 in words is "sixty-one billion, nine hundred seventy-seven million, seven hundred ninety-four thousand, seven hundred ninety".