64536391 has 2 divisors, whose sum is σ = 64536392. Its totient is φ = 64536390.

The previous prime is 64536371. The next prime is 64536463. The reversal of 64536391 is 19363546.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 64536391 - 2⁵ = 64536359 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 64536391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64536341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32268195 + 32268196.

It is an arithmetic number, because the mean of its divisors is an integer number (32268196).

Almost surely, 2^64536391 is an apocalyptic number.

64536391 is a deficient number, since it is larger than the sum of its proper divisors (1).

64536391 is an equidigital number, since it uses as much as digits as its factorization.

64536391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 58320, while the sum is 37.

The square root of 64536391 is about 8033.4544873298. The cubic root of 64536391 is about 401.1143737946.

The spelling of 64536391 in words is "sixty-four million, five hundred thirty-six thousand, three hundred ninety-one".