21323984 has 40 divisors (see below), whose sum is σ = 47729088. Its totient is φ = 9121280.

The previous prime is 21323983. The next prime is 21323989. The reversal of 21323984 is 48932312.

21323984 = T₃₈₁ + T₃₈₂ + ... + T₅₆₇.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21323984.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21323983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 572 + ... + 6555.

Almost surely, 2^21323984 is an apocalyptic number.

It is an amenable number.

21323984 is an abundant number, since it is smaller than the sum of its proper divisors (26405104).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21323984 is a wasteful number, since it uses less digits than its factorization.

21323984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7163 (or 7157 counting only the distinct ones).

The product of its digits is 10368, while the sum is 32.

The square root of 21323984 is about 4617.7899475832. The cubic root of 21323984 is about 277.3039884097.

It can be divided in two parts, 2132 and 3984, that added together give a palindrome (6116).

The spelling of 21323984 in words is "twenty-one million, three hundred twenty-three thousand, nine hundred eighty-four".