21197120600 has 24 divisors (see below), whose sum is σ = 49283305860. Its totient is φ = 8478848160.

The previous prime is 21197120507. The next prime is 21197120603. The reversal of 21197120600 is 602179112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21197120603) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 52992602 + ... + 52993001.

Almost surely, 2^21197120600 is an apocalyptic number.

21197120600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21197120600 is an abundant number, since it is smaller than the sum of its proper divisors (28086185260).

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

21197120600 is a wasteful number, since it uses less digits than its factorization.

21197120600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105985619 (or 105985610 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 29.

Adding to 21197120600 its reverse (602179112), we get a palindrome (21799299712).

The spelling of 21197120600 in words is "twenty-one billion, one hundred ninety-seven million, one hundred twenty thousand, six hundred".