21732656400 has 1215 divisors, whose sum is σ = 98648063631. Its totient is φ = 4585351680.

The previous prime is 21732656383. The next prime is 21732656417. The reversal of 21732656400 is 465623712.

The square root of 21732656400 is 147420.

It is a perfect power (a square), and thus also a powerful number.

21732656400 is a `hidden beast` number, since 2 + 1 + 7 + 3 + 2 + 6 + 5 + 640 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (21732656383) and next prime (21732656417).

It can be written as a sum of positive squares in 4 ways, for example, as 5601624336 + 16131032064 = 74844^2 + 127008^2 .

It is a tau number, because it is divible by the number of its divisors (1215).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 242 ways as a sum of consecutive naturals, for example, 1671742794 + ... + 1671742806.

Almost surely, 2^21732656400 is an apocalyptic number.

21732656400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

21732656400 is the 147420-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21732656400

21732656400 is an abundant number, since it is smaller than the sum of its proper divisors (76915407231).

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

21732656400 is an equidigital number, since it uses as much as digits as its factorization.

21732656400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82 (or 30 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

Multiplying 21732656400 by its sum of digits (36), we get a square (782375630400 = 884520²).

21732656400 divided by its sum of digits (36) gives a square (603684900 = 24570²).

The spelling of 21732656400 in words is "twenty-one billion, seven hundred thirty-two million, six hundred fifty-six thousand, four hundred".