21130021200 has 60 divisors (see below), whose sum is σ = 67686505088. Its totient is φ = 5634672000.

The previous prime is 21130021183. The next prime is 21130021219. The reversal of 21130021200 is 212003112.

It is a tau number, because it is divible by the number of its divisors (60).

It is a super-3 number, since 3×21130021200³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8802976 + ... + 8805375.

Almost surely, 2^21130021200 is an apocalyptic number.

21130021200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21130021200 is an abundant number, since it is smaller than the sum of its proper divisors (46556483888).

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

21130021200 is a wasteful number, since it uses less digits than its factorization.

21130021200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17608372 (or 17608361 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21130021200 its reverse (212003112), we get a palindrome (21342024312).

The spelling of 21130021200 in words is "twenty-one billion, one hundred thirty million, twenty-one thousand, two hundred".