21377984 has 14 divisors (see below), whose sum is σ = 42422064. Its totient is φ = 10688960.

The previous prime is 21377981. The next prime is 21378011. The reversal of 21377984 is 48977312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21377981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166952 + ... + 167079.

Almost surely, 2^21377984 is an apocalyptic number.

It is an amenable number.

21377984 is a deficient number, since it is larger than the sum of its proper divisors (21044080).

21377984 is an equidigital number, since it uses as much as digits as its factorization.

21377984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334043 (or 334033 counting only the distinct ones).

The product of its digits is 84672, while the sum is 41.

The square root of 21377984 is about 4623.6332034451. The cubic root of 21377984 is about 277.5378689223.

The spelling of 21377984 in words is "twenty-one million, three hundred seventy-seven thousand, nine hundred eighty-four".