21153623400 has 864 divisors, whose sum is σ = 93776810400. Its totient is φ = 4223923200.

The previous prime is 21153623383. The next prime is 21153623401. The reversal of 21153623400 is 432635112.

21153623400 is a `hidden beast` number, since 21 + 15 + 3 + 623 + 4 + 0 + 0 = 666.

It is not an unprimeable number, because it can be changed into a prime (21153623401) 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 215 ways as a sum of consecutive naturals, for example, 21784915 + ... + 21785885.

It is an arithmetic number, because the mean of its divisors is an integer number (108537975).

Almost surely, 2^21153623400 is an apocalyptic number.

21153623400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21153623400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46888405200).

21153623400 is an abundant number, since it is smaller than the sum of its proper divisors (72623187000).

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

21153623400 is a wasteful number, since it uses less digits than its factorization.

21153623400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1039 (or 1020 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The spelling of 21153623400 in words is "twenty-one billion, one hundred fifty-three million, six hundred twenty-three thousand, four hundred".