21853404 has 36 divisors (see below), whose sum is σ = 57644496. Its totient is φ = 6967488.

The previous prime is 21853399. The next prime is 21853487. The reversal of 21853404 is 40435812.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12369 + ... + 14024.

It is an arithmetic number, because the mean of its divisors is an integer number (1601236).

Almost surely, 2^21853404 is an apocalyptic number.

It is an amenable number.

21853404 is an abundant number, since it is smaller than the sum of its proper divisors (35791092).

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

21853404 is a wasteful number, since it uses less digits than its factorization.

21853404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26426 (or 26421 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 21853404 is about 4674.7624538579. The cubic root of 21853404 is about 279.5801701447.

The spelling of 21853404 in words is "twenty-one million, eight hundred fifty-three thousand, four hundred four".