21120911200 has 36 divisors (see below), whose sum is σ = 51561426420. Its totient is φ = 8448364160.

The previous prime is 21120911173. The next prime is 21120911209. The reversal of 21120911200 is 211902112.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120911209) 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, 13199770 + ... + 13201369.

It is an arithmetic number, because the mean of its divisors is an integer number (1432261845).

Almost surely, 2^21120911200 is an apocalyptic number.

21120911200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120911200 is an abundant number, since it is smaller than the sum of its proper divisors (30440515220).

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

21120911200 is a wasteful number, since it uses less digits than its factorization.

21120911200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26401159 (or 26401146 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 21120911200 in words is "twenty-one billion, one hundred twenty million, nine hundred eleven thousand, two hundred".