21815270400 has 1584 divisors, whose sum is σ = 100004170752. Its totient is φ = 4128768000.

The previous prime is 21815270381. The next prime is 21815270429. The reversal of 21815270400 is 407251812.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 703718385 + ... + 703718415.

Almost surely, 2^21815270400 is an apocalyptic number.

21815270400 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 21815270400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50002085376).

21815270400 is an abundant number, since it is smaller than the sum of its proper divisors (78188900352).

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

21815270400 is a wasteful number, since it uses less digits than its factorization.

21815270400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 30.

The spelling of 21815270400 in words is "twenty-one billion, eight hundred fifteen million, two hundred seventy thousand, four hundred".