21453876 has 24 divisors (see below), whose sum is σ = 55621440. Its totient is φ = 7151256.

The previous prime is 21453853. The next prime is 21453877. The reversal of 21453876 is 67835412.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 21453876.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21453877) 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, 99216 + ... + 99431.

It is an arithmetic number, because the mean of its divisors is an integer number (2317560).

Almost surely, 2^21453876 is an apocalyptic number.

It is an amenable number.

21453876 is an abundant number, since it is smaller than the sum of its proper divisors (34167564).

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

21453876 is a wasteful number, since it uses less digits than its factorization.

21453876 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198660 (or 198652 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 21453876 is about 4631.8328985403. The cubic root of 21453876 is about 277.8659015454.

The spelling of 21453876 in words is "twenty-one million, four hundred fifty-three thousand, eight hundred seventy-six".