51631961 has 2 divisors, whose sum is σ = 51631962. Its totient is φ = 51631960.

The previous prime is 51631901. The next prime is 51632039. The reversal of 51631961 is 16913615.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39942400 + 11689561 = 6320^2 + 3419^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51631961 is a prime.

It is a Chen prime.

It is equal to p_3093089 and since 51631961 and 3093089 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (51631901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25815980 + 25815981.

It is an arithmetic number, because the mean of its divisors is an integer number (25815981).

Almost surely, 2^51631961 is an apocalyptic number.

It is an amenable number.

51631961 is a deficient number, since it is larger than the sum of its proper divisors (1).

51631961 is an equidigital number, since it uses as much as digits as its factorization.

51631961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4860, while the sum is 32.

The square root of 51631961 is about 7185.5383236053. The cubic root of 51631961 is about 372.3684468569.

The spelling of 51631961 in words is "fifty-one million, six hundred thirty-one thousand, nine hundred sixty-one".