61915931 has 16 divisors (see below), whose sum is σ = 80552448. Its totient is φ = 46147200.

The previous prime is 61915901. The next prime is 61915939. The reversal of 61915931 is 13951916.

61915931 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-61915931 is a prime.

It is a super-2 number, since 2×61915931² = 7667165023193522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61915891 and 61915900.

It is not an unprimeable number, because it can be changed into a prime (61915939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15710 + ... + 19251.

It is an arithmetic number, because the mean of its divisors is an integer number (5034528).

Almost surely, 2^61915931 is an apocalyptic number.

61915931 is a deficient number, since it is larger than the sum of its proper divisors (18636517).

61915931 is a wasteful number, since it uses less digits than its factorization.

61915931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35002.

The product of its digits is 7290, while the sum is 35.

The square root of 61915931 is about 7868.6676762969. The cubic root of 61915931 is about 395.6101897345.

The spelling of 61915931 in words is "sixty-one million, nine hundred fifteen thousand, nine hundred thirty-one".