21453524400 has 480 divisors, whose sum is σ = 86794444800. Its totient is φ = 4399948800.

The previous prime is 21453524311. The next prime is 21453524401. The reversal of 21453524400 is 442535412.

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

It is not an unprimeable number, because it can be changed into a prime (21453524401) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 7298131 + ... + 7301069.

It is an arithmetic number, because the mean of its divisors is an integer number (180821760).

Almost surely, 2^21453524400 is an apocalyptic number.

21453524400 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 21453524400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43397222400).

21453524400 is an abundant number, since it is smaller than the sum of its proper divisors (65340920400).

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

21453524400 is a wasteful number, since it uses less digits than its factorization.

21453524400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3057 (or 3046 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 30.

The spelling of 21453524400 in words is "twenty-one billion, four hundred fifty-three million, five hundred twenty-four thousand, four hundred".