21887804 has 12 divisors (see below), whose sum is σ = 38353224. Its totient is φ = 10929744.

The previous prime is 21887797. The next prime is 21887807. The reversal of 21887804 is 40878812.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21887807) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 434 + ... + 6630.

It is an arithmetic number, because the mean of its divisors is an integer number (3196102).

Almost surely, 2^21887804 is an apocalyptic number.

It is an amenable number.

21887804 is a deficient number, since it is larger than the sum of its proper divisors (16465420).

21887804 is a wasteful number, since it uses less digits than its factorization.

21887804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7084 (or 7082 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 38.

The square root of 21887804 is about 4678.4403384034. The cubic root of 21887804 is about 279.7267913278.

The spelling of 21887804 in words is "twenty-one million, eight hundred eighty-seven thousand, eight hundred four".