21200697504 has 216 divisors, whose sum is σ = 71324154720. Its totient is φ = 5954441472.

The previous prime is 21200697499. The next prime is 21200697523. The reversal of 21200697504 is 40579600212.

It is a super-2 number, since 2×21200697504² (a number of 21 digits) contains 22 as substring.

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 35 ways as a sum of consecutive naturals, for example, 819877 + ... + 845339.

It is an arithmetic number, because the mean of its divisors is an integer number (330204420).

Almost surely, 2^21200697504 is an apocalyptic number.

21200697504 is a gapful number since it is divisible by the number (24) 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 21200697504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35662077360).

21200697504 is an abundant number, since it is smaller than the sum of its proper divisors (50123457216).

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

21200697504 is a wasteful number, since it uses less digits than its factorization.

21200697504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25552 (or 25534 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The spelling of 21200697504 in words is "twenty-one billion, two hundred million, six hundred ninety-seven thousand, five hundred four".