64961931 has 8 divisors (see below), whose sum is σ = 91174720. Its totient is φ = 41028552.

The previous prime is 64961881. The next prime is 64961977. The reversal of 64961931 is 13916946.

64961931 = 254² + 255² + ... + 595².

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64961931 - 2¹³ = 64953739 is a prime.

It is a super-2 number, since 2×64961931² = 8440104958497522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64961931.

It is not an unprimeable number, because it can be changed into a prime (64961231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 569785 + ... + 569898.

It is an arithmetic number, because the mean of its divisors is an integer number (11396840).

Almost surely, 2^64961931 is an apocalyptic number.

64961931 is a deficient number, since it is larger than the sum of its proper divisors (26212789).

64961931 is a wasteful number, since it uses less digits than its factorization.

64961931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1139705.

The product of its digits is 34992, while the sum is 39.

The square root of 64961931 is about 8059.8964633548. The cubic root of 64961931 is about 401.9940656533.

The spelling of 64961931 in words is "sixty-four million, nine hundred sixty-one thousand, nine hundred thirty-one".