21623804 has 12 divisors (see below), whose sum is σ = 38093328. Its totient is φ = 10740000.

The previous prime is 21623803. The next prime is 21623809. The reversal of 21623804 is 40832612.

It is a super-3 number, since 3×21623804³ (a number of 23 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21623803) 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, 17297 + ... + 18504.

It is an arithmetic number, because the mean of its divisors is an integer number (3174444).

Almost surely, 2^21623804 is an apocalyptic number.

It is an amenable number.

21623804 is a deficient number, since it is larger than the sum of its proper divisors (16469524).

21623804 is a wasteful number, since it uses less digits than its factorization.

21623804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35956 (or 35954 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 21623804 is about 4650.1402129398. The cubic root of 21623804 is about 278.5975965149.

The spelling of 21623804 in words is "twenty-one million, six hundred twenty-three thousand, eight hundred four".