52991581 has 2 divisors, whose sum is σ = 52991582. Its totient is φ = 52991580.

The previous prime is 52991531. The next prime is 52991591. The reversal of 52991581 is 18519925.

52991581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42968025 + 10023556 = 6555^2 + 3166^2 .

It is a cyclic number.

It is not a de Polignac number, because 52991581 - 2⁷ = 52991453 is a prime.

It is a super-2 number, since 2×52991581² = 5616215313759122, 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 (52991501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26495790 + 26495791.

It is an arithmetic number, because the mean of its divisors is an integer number (26495791).

Almost surely, 2^52991581 is an apocalyptic number.

It is an amenable number.

52991581 is a deficient number, since it is larger than the sum of its proper divisors (1).

52991581 is an equidigital number, since it uses as much as digits as its factorization.

52991581 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32400, while the sum is 40.

The square root of 52991581 is about 7279.5316470224. The cubic root of 52991581 is about 375.6086849539.

The spelling of 52991581 in words is "fifty-two million, nine hundred ninety-one thousand, five hundred eighty-one".