387664591 has 2 divisors, whose sum is σ = 387664592. Its totient is φ = 387664590.

The previous prime is 387664573. The next prime is 387664637. The reversal of 387664591 is 195466783.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 387664591 - 2⁵ = 387664559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (387664561) 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, 193832295 + 193832296.

It is an arithmetic number, because the mean of its divisors is an integer number (193832296).

Almost surely, 2^387664591 is an apocalyptic number.

387664591 is a deficient number, since it is larger than the sum of its proper divisors (1).

387664591 is an equidigital number, since it uses as much as digits as its factorization.

387664591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1088640, while the sum is 49.

The square root of 387664591 is about 19689.1998567743. The cubic root of 387664591 is about 729.1530748480.

The spelling of 387664591 in words is "three hundred eighty-seven million, six hundred sixty-four thousand, five hundred ninety-one".