51897631 has 2 divisors, whose sum is σ = 51897632. Its totient is φ = 51897630.

The previous prime is 51897613. The next prime is 51897647. The reversal of 51897631 is 13679815.

Together with previous prime (51897613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51897631 - 2⁹ = 51897119 is a prime.

It is a super-2 number, since 2×51897631² = 5386728206824322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51897611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25948815 + 25948816.

It is an arithmetic number, because the mean of its divisors is an integer number (25948816).

Almost surely, 2^51897631 is an apocalyptic number.

51897631 is a deficient number, since it is larger than the sum of its proper divisors (1).

51897631 is an equidigital number, since it uses as much as digits as its factorization.

51897631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 40.

The square root of 51897631 is about 7204.0010410882. The cubic root of 51897631 is about 373.0060230899.

The spelling of 51897631 in words is "fifty-one million, eight hundred ninety-seven thousand, six hundred thirty-one".