21461804 has 36 divisors (see below), whose sum is σ = 47056464. Its totient is φ = 8489376.

The previous prime is 21461789. The next prime is 21461821. The reversal of 21461804 is 40816412.

It is a Harshad number since it is a multiple of its sum of digits (26).

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, 1664 + ... + 6759.

It is an arithmetic number, because the mean of its divisors is an integer number (1307124).

Almost surely, 2^21461804 is an apocalyptic number.

It is an amenable number.

21461804 is an abundant number, since it is smaller than the sum of its proper divisors (25594660).

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

21461804 is a wasteful number, since it uses less digits than its factorization.

21461804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8454 (or 8445 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 21461804 is about 4632.6886362025. The cubic root of 21461804 is about 277.9001245698.

The spelling of 21461804 in words is "twenty-one million, four hundred sixty-one thousand, eight hundred four".