61860721836 has 48 divisors (see below), whose sum is σ = 149044654080. Its totient is φ = 19948805760.

The previous prime is 61860721829. The next prime is 61860721841. The reversal of 61860721836 is 63812706816.

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, 1243000 + ... + 1291808.

It is an arithmetic number, because the mean of its divisors is an integer number (3105096960).

Almost surely, 2^61860721836 is an apocalyptic number.

It is an amenable number.

61860721836 is an abundant number, since it is smaller than the sum of its proper divisors (87183932244).

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

61860721836 is a wasteful number, since it uses less digits than its factorization.

61860721836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52254 (or 52252 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 48.

The spelling of 61860721836 in words is "sixty-one billion, eight hundred sixty million, seven hundred twenty-one thousand, eight hundred thirty-six".