21055454400 has 84 divisors (see below), whose sum is σ = 69079452392. Its totient is φ = 5614786560.

The previous prime is 21055454393. The next prime is 21055454461. The reversal of 21055454400 is 445455012.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2188477 + ... + 2198076.

Almost surely, 2^21055454400 is an apocalyptic number.

21055454400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21055454400 is an abundant number, since it is smaller than the sum of its proper divisors (48023997992).

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

21055454400 is a wasteful number, since it uses less digits than its factorization.

21055454400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4386578 (or 4386563 counting only the distinct ones).

The product of its (nonzero) digits is 16000, while the sum is 30.

The spelling of 21055454400 in words is "twenty-one billion, fifty-five million, four hundred fifty-four thousand, four hundred".