21479404 has 24 divisors (see below), whose sum is σ = 39287808. Its totient is φ = 10263120.

The previous prime is 21479377. The next prime is 21479407. The reversal of 21479404 is 40497412.

It is a super-2 number, since 2×21479404² = 922729592390432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (21479407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9249 + ... + 11335.

It is an arithmetic number, because the mean of its divisors is an integer number (1636992).

Almost surely, 2^21479404 is an apocalyptic number.

It is an amenable number.

21479404 is a deficient number, since it is larger than the sum of its proper divisors (17808404).

21479404 is a wasteful number, since it uses less digits than its factorization.

21479404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2205 (or 2203 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 21479404 is about 4634.5877918106. The cubic root of 21479404 is about 277.9760688818.

The spelling of 21479404 in words is "twenty-one million, four hundred seventy-nine thousand, four hundred four".