52156781 has 2 divisors, whose sum is σ = 52156782. Its totient is φ = 52156780.

The previous prime is 52156751. The next prime is 52156837. The reversal of 52156781 is 18765125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48580900 + 3575881 = 6970^2 + 1891^2 .

It is a cyclic number.

It is not a de Polignac number, because 52156781 - 2²² = 47962477 is a prime.

It is a super-2 number, since 2×52156781² = 5440659608563922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (52156751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26078390 + 26078391.

It is an arithmetic number, because the mean of its divisors is an integer number (26078391).

Almost surely, 2^52156781 is an apocalyptic number.

It is an amenable number.

52156781 is a deficient number, since it is larger than the sum of its proper divisors (1).

52156781 is an equidigital number, since it uses as much as digits as its factorization.

52156781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16800, while the sum is 35.

The square root of 52156781 is about 7221.9651757676. The cubic root of 52156781 is about 373.6258590781.

The spelling of 52156781 in words is "fifty-two million, one hundred fifty-six thousand, seven hundred eighty-one".