51913631 has 16 divisors (see below), whose sum is σ = 68532480. Its totient is φ = 38071680.

The previous prime is 51913621. The next prime is 51913633. The reversal of 51913631 is 13631915.

51913631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 51913631 - 2²² = 47719327 is a prime.

It is a super-2 number, since 2×51913631² = 5390050167208322, 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 = 51913594 and 51913603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51913633) 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, 18521 + ... + 21138.

It is an arithmetic number, because the mean of its divisors is an integer number (4283280).

Almost surely, 2^51913631 is an apocalyptic number.

51913631 is a deficient number, since it is larger than the sum of its proper divisors (16618849).

51913631 is a wasteful number, since it uses less digits than its factorization.

51913631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39694.

The product of its digits is 2430, while the sum is 29.

The square root of 51913631 is about 7205.1114495197. Note that the first 3 decimals coincide. The cubic root of 51913631 is about 373.0443516419.

The spelling of 51913631 in words is "fifty-one million, nine hundred thirteen thousand, six hundred thirty-one".