21054504120 has 64 divisors (see below), whose sum is σ = 68022249120. Its totient is φ = 5182646784.

The previous prime is 21054504113. The next prime is 21054504139. The reversal of 21054504120 is 2140545012.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 6746679 + ... + 6749798.

Almost surely, 2^21054504120 is an apocalyptic number.

21054504120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21054504120 is an abundant number, since it is smaller than the sum of its proper divisors (46967745000).

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

21054504120 is a wasteful number, since it uses less digits than its factorization.

21054504120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13496504 (or 13496500 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 24.

The spelling of 21054504120 in words is "twenty-one billion, fifty-four million, five hundred four thousand, one hundred twenty".