21477804 has 24 divisors (see below), whose sum is σ = 50190000. Its totient is φ = 7148544.

The previous prime is 21477803. The next prime is 21477811. The reversal of 21477804 is 40877412.

It is a super-2 number, since 2×21477804² = 922592129324832, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21477803) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14272 + ... + 15704.

It is an arithmetic number, because the mean of its divisors is an integer number (2091250).

Almost surely, 2^21477804 is an apocalyptic number.

It is an amenable number.

21477804 is an abundant number, since it is smaller than the sum of its proper divisors (28712196).

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

21477804 is a wasteful number, since it uses less digits than its factorization.

21477804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2689 (or 2687 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 33.

The square root of 21477804 is about 4634.4151734604. The cubic root of 21477804 is about 277.9691665681.

The spelling of 21477804 in words is "twenty-one million, four hundred seventy-seven thousand, eight hundred four".