64981831 has 6 divisors (see below), whose sum is σ = 67930520. Its totient is φ = 62156028.

The previous prime is 64981817. The next prime is 64981867. The reversal of 64981831 is 13818946.

It is not a de Polignac number, because 64981831 - 2⁵ = 64981799 is a prime.

It is a super-2 number, since 2×64981831² = 8445276720225122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64981811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 60891 + ... + 61948.

Almost surely, 2^64981831 is an apocalyptic number.

64981831 is a deficient number, since it is larger than the sum of its proper divisors (2948689).

64981831 is a wasteful number, since it uses less digits than its factorization.

64981831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122885 (or 122862 counting only the distinct ones).

The product of its digits is 41472, while the sum is 40.

The square root of 64981831 is about 8061.1308760000. The cubic root of 64981831 is about 402.0351095133.

The spelling of 64981831 in words is "sixty-four million, nine hundred eighty-one thousand, eight hundred thirty-one".