51537881 has 2 divisors, whose sum is σ = 51537882. Its totient is φ = 51537880.

The previous prime is 51537851. The next prime is 51537907. The reversal of 51537881 is 18873515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50537881 + 1000000 = 7109^2 + 1000^2 .

It is a cyclic number.

It is not a de Polignac number, because 51537881 - 2⁶ = 51537817 is a prime.

It is a super-2 number, since 2×51537881² = 5312306355940322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (51537851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25768940 + 25768941.

It is an arithmetic number, because the mean of its divisors is an integer number (25768941).

Almost surely, 2^51537881 is an apocalyptic number.

It is an amenable number.

51537881 is a deficient number, since it is larger than the sum of its proper divisors (1).

51537881 is an equidigital number, since it uses as much as digits as its factorization.

51537881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 33600, while the sum is 38.

The square root of 51537881 is about 7178.9888563780. The cubic root of 51537881 is about 372.1421417918.

The spelling of 51537881 in words is "fifty-one million, five hundred thirty-seven thousand, eight hundred eighty-one".