64377021 has 24 divisors (see below), whose sum is σ = 89581440. Its totient is φ = 41109120.

The previous prime is 64376999. The next prime is 64377029. The reversal of 64377021 is 12077346.

It is not a de Polignac number, because 64377021 - 2¹⁸ = 64114877 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 64377021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64377029) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 814860 + ... + 814938.

It is an arithmetic number, because the mean of its divisors is an integer number (3732560).

Almost surely, 2^64377021 is an apocalyptic number.

64377021 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

64377021 is a deficient number, since it is larger than the sum of its proper divisors (25204419).

64377021 is an equidigital number, since it uses as much as digits as its factorization.

64377021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 30.

The square root of 64377021 is about 8023.5292110143. The cubic root of 64377021 is about 400.7839230746.

The spelling of 64377021 in words is "sixty-four million, three hundred seventy-seven thousand, twenty-one".