51838781 has 2 divisors, whose sum is σ = 51838782. Its totient is φ = 51838780.

The previous prime is 51838769. The next prime is 51838807. The reversal of 51838781 is 18783815.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51768025 + 70756 = 7195^2 + 266^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51838781 is a prime.

It is a super-2 number, since 2×51838781² = 5374518431131922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51838741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25919390 + 25919391.

It is an arithmetic number, because the mean of its divisors is an integer number (25919391).

Almost surely, 2^51838781 is an apocalyptic number.

It is an amenable number.

51838781 is a deficient number, since it is larger than the sum of its proper divisors (1).

51838781 is an equidigital number, since it uses as much as digits as its factorization.

51838781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 41.

The square root of 51838781 is about 7199.9153467246. The cubic root of 51838781 is about 372.8649780709.

The spelling of 51838781 in words is "fifty-one million, eight hundred thirty-eight thousand, seven hundred eighty-one".