65931381 has 32 divisors (see below), whose sum is σ = 100131840. Its totient is φ = 42865200.

The previous prime is 65931377. The next prime is 65931401. The reversal of 65931381 is 18313956.

It is a happy number.

It is not a de Polignac number, because 65931381 - 2² = 65931377 is a prime.

It is a super-2 number, since 2×65931381² = 8693894001134322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65931361) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 312366 + ... + 312576.

It is an arithmetic number, because the mean of its divisors is an integer number (3129120).

Almost surely, 2^65931381 is an apocalyptic number.

It is an amenable number.

65931381 is a deficient number, since it is larger than the sum of its proper divisors (34200459).

65931381 is a wasteful number, since it uses less digits than its factorization.

65931381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 454 (or 448 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 65931381 is about 8119.8140988572. The cubic root of 65931381 is about 403.9839000381.

The spelling of 65931381 in words is "sixty-five million, nine hundred thirty-one thousand, three hundred eighty-one".