21223505400 has 96 divisors (see below), whose sum is σ = 69255686400. Its totient is φ = 5361724800.

The previous prime is 21223505383. The next prime is 21223505411. The reversal of 21223505400 is 450532212.

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 23 ways as a sum of consecutive naturals, for example, 919456 + ... + 942255.

It is an arithmetic number, because the mean of its divisors is an integer number (721413400).

Almost surely, 2^21223505400 is an apocalyptic number.

21223505400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21223505400 is an abundant number, since it is smaller than the sum of its proper divisors (48032181000).

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

21223505400 is a wasteful number, since it uses less digits than its factorization.

21223505400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1861749 (or 1861740 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 24.

The spelling of 21223505400 in words is "twenty-one billion, two hundred twenty-three million, five hundred five thousand, four hundred".