61551511986 has 64 divisors (see below), whose sum is σ = 129277969920. Its totient is φ = 19514039040.

The previous prime is 61551511969. The next prime is 61551511991. The reversal of 61551511986 is 68911515516.

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, 9815260 + ... + 9821528.

It is an arithmetic number, because the mean of its divisors is an integer number (2019968280).

Almost surely, 2^61551511986 is an apocalyptic number.

61551511986 is an abundant number, since it is smaller than the sum of its proper divisors (67726457934).

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

61551511986 is a wasteful number, since it uses less digits than its factorization.

61551511986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7299.

The product of its digits is 324000, while the sum is 48.

The spelling of 61551511986 in words is "sixty-one billion, five hundred fifty-one million, five hundred eleven thousand, nine hundred eighty-six".