21458804 has 6 divisors (see below), whose sum is σ = 37552914. Its totient is φ = 10729400.

The previous prime is 21458803. The next prime is 21458807. The reversal of 21458804 is 40885412.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 21436900 + 21904 = 4630^2 + 148^2 .

It is a super-2 number, since 2×21458804² = 920960538220832, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21458803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2682347 + ... + 2682354.

It is an arithmetic number, because the mean of its divisors is an integer number (6258819).

Almost surely, 2^21458804 is an apocalyptic number.

It is an amenable number.

21458804 is a deficient number, since it is larger than the sum of its proper divisors (16094110).

21458804 is a wasteful number, since it uses less digits than its factorization.

21458804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5364705 (or 5364703 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 32.

The square root of 21458804 is about 4632.3648388269. The cubic root of 21458804 is about 277.8871753753.

The spelling of 21458804 in words is "twenty-one million, four hundred fifty-eight thousand, eight hundred four".