21554287400 has 48 divisors (see below), whose sum is σ = 50191475040. Its totient is φ = 8608337600.

The previous prime is 21554287361. The next prime is 21554287427. The reversal of 21554287400 is 478245512.

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, 46115 + ... + 212685.

It is an arithmetic number, because the mean of its divisors is an integer number (1045655730).

Almost surely, 2^21554287400 is an apocalyptic number.

21554287400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21554287400 is an abundant number, since it is smaller than the sum of its proper divisors (28637187640).

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

21554287400 is a wasteful number, since it uses less digits than its factorization.

21554287400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167234 (or 167225 counting only the distinct ones).

The product of its (nonzero) digits is 89600, while the sum is 38.

The spelling of 21554287400 in words is "twenty-one billion, five hundred fifty-four million, two hundred eighty-seven thousand, four hundred".