52401991 has 2 divisors, whose sum is σ = 52401992. Its totient is φ = 52401990.

The previous prime is 52401917. The next prime is 52402033. The reversal of 52401991 is 19910425.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 52401991 - 2⁷ = 52401863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (52401901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26200995 + 26200996.

It is an arithmetic number, because the mean of its divisors is an integer number (26200996).

Almost surely, 2^52401991 is an apocalyptic number.

52401991 is a deficient number, since it is larger than the sum of its proper divisors (1).

52401991 is an equidigital number, since it uses as much as digits as its factorization.

52401991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 31.

The square root of 52401991 is about 7238.9219501249. The cubic root of 52401991 is about 374.2104656762.

The spelling of 52401991 in words is "fifty-two million, four hundred one thousand, nine hundred ninety-one".