21054590404 has 9 divisors (see below), whose sum is σ = 36846041071. Its totient is φ = 10527150100.

The previous prime is 21054590399. The next prime is 21054590407. The reversal of 21054590404 is 40409545012.

The square root of 21054590404 is 145102.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21054590404.

It is not an unprimeable number, because it can be changed into a prime (21054590407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 253929 + ... + 326479.

Almost surely, 2^21054590404 is an apocalyptic number.

21054590404 is the 145102-nd square number.

It is an amenable number.

21054590404 is a deficient number, since it is larger than the sum of its proper divisors (15791450667).

21054590404 is an frugal number, since it uses more digits than its factorization.

21054590404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145106 (or 72553 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 34.

The spelling of 21054590404 in words is "twenty-one billion, fifty-four million, five hundred ninety thousand, four hundred four".