21532562100 has 720 divisors, whose sum is σ = 85753261440. Its totient is φ = 4561920000.

The previous prime is 21532562063. The next prime is 21532562101. The reversal of 21532562100 is 126523512.

It is a happy number.

21532562100 is a `hidden beast` number, since 2 + 1 + 5 + 32 + 5 + 621 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21532562101) by changing a digit.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 85786975 + ... + 85787225.

It is an arithmetic number, because the mean of its divisors is an integer number (119101752).

Almost surely, 2^21532562100 is an apocalyptic number.

21532562100 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 21532562100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42876630720).

21532562100 is an abundant number, since it is smaller than the sum of its proper divisors (64220699340).

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

21532562100 is a wasteful number, since it uses less digits than its factorization.

21532562100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 390 (or 374 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The spelling of 21532562100 in words is "twenty-one billion, five hundred thirty-two million, five hundred sixty-two thousand, one hundred".