61981051321 has 16 divisors (see below), whose sum is σ = 71478126720. Its totient is φ = 52646002560.

The previous prime is 61981051309. The next prime is 61981051351. The reversal of 61981051321 is 12315018916.

It is a cyclic number.

It is not a de Polignac number, because 61981051321 - 2⁷ = 61981051193 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61981051351) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 490995 + ... + 604183.

It is an arithmetic number, because the mean of its divisors is an integer number (4467382920).

Almost surely, 2^61981051321 is an apocalyptic number.

It is an amenable number.

61981051321 is a deficient number, since it is larger than the sum of its proper divisors (9497075399).

61981051321 is a wasteful number, since it uses less digits than its factorization.

61981051321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113904.

The product of its (nonzero) digits is 12960, while the sum is 37.

The spelling of 61981051321 in words is "sixty-one billion, nine hundred eighty-one million, fifty-one thousand, three hundred twenty-one".