61797879816 has 64 divisors (see below), whose sum is σ = 159351753600. Its totient is φ = 19956469248.

The previous prime is 61797879763. The next prime is 61797879823. The reversal of 61797879816 is 61897879716.

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, 57565 + ... + 356243.

It is an arithmetic number, because the mean of its divisors is an integer number (2489871150).

Almost surely, 2^61797879816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61797879816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79675876800).

61797879816 is an abundant number, since it is smaller than the sum of its proper divisors (97553873784).

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

61797879816 is a wasteful number, since it uses less digits than its factorization.

61797879816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298958 (or 298954 counting only the distinct ones).

The product of its digits is 64012032, while the sum is 69.

The spelling of 61797879816 in words is "sixty-one billion, seven hundred ninety-seven million, eight hundred seventy-nine thousand, eight hundred sixteen".