51316631 has 4 divisors (see below), whose sum is σ = 53086200. Its totient is φ = 49547064.

The previous prime is 51316627. The next prime is 51316633. The reversal of 51316631 is 13661315.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51316631 - 2² = 51316627 is a prime.

It is a super-2 number, since 2×51316631² = 5266793234380322, 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 51316631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51316633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 884741 + ... + 884798.

It is an arithmetic number, because the mean of its divisors is an integer number (13271550).

Almost surely, 2^51316631 is an apocalyptic number.

51316631 is a deficient number, since it is larger than the sum of its proper divisors (1769569).

51316631 is a wasteful number, since it uses less digits than its factorization.

51316631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1769568.

The product of its digits is 1620, while the sum is 26.

The square root of 51316631 is about 7163.5627309321. The cubic root of 51316631 is about 371.6088476309.

Adding to 51316631 its reverse (13661315), we get a palindrome (64977946).

The spelling of 51316631 in words is "fifty-one million, three hundred sixteen thousand, six hundred thirty-one".