21461604 has 24 divisors (see below), whose sum is σ = 50927520. Its totient is φ = 7032384.

The previous prime is 21461593. The next prime is 21461611. The reversal of 21461604 is 40616412.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14449 + ... + 15864.

It is an arithmetic number, because the mean of its divisors is an integer number (2121980).

Almost surely, 2^21461604 is an apocalyptic number.

It is an amenable number.

21461604 is an abundant number, since it is smaller than the sum of its proper divisors (29465916).

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

21461604 is a wasteful number, since it uses less digits than its factorization.

21461604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30379 (or 30377 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 21461604 is about 4632.6670504149. The cubic root of 21461604 is about 277.8992613277.

The spelling of 21461604 in words is "twenty-one million, four hundred sixty-one thousand, six hundred four".