21377464 has 8 divisors (see below), whose sum is σ = 40082760. Its totient is φ = 10688728.

The previous prime is 21377459. The next prime is 21377501. The reversal of 21377464 is 46477312.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1336084 + ... + 1336099.

It is an arithmetic number, because the mean of its divisors is an integer number (5010345).

Almost surely, 2^21377464 is an apocalyptic number.

It is an amenable number.

21377464 is a deficient number, since it is larger than the sum of its proper divisors (18705296).

21377464 is a wasteful number, since it uses less digits than its factorization.

21377464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2672189 (or 2672185 counting only the distinct ones).

The product of its digits is 28224, while the sum is 34.

The square root of 21377464 is about 4623.5769702688. The cubic root of 21377464 is about 277.5356186187.

It can be divided in two parts, 213 and 77464, that added together give a palindrome (77677).

The spelling of 21377464 in words is "twenty-one million, three hundred seventy-seven thousand, four hundred sixty-four".