21144501200 has 30 divisors (see below), whose sum is σ = 50799665094. Its totient is φ = 8457800320.

The previous prime is 21144501163. The next prime is 21144501211. The reversal of 21144501200 is 210544112.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 6641598016 + 14502903184 = 81496^2 + 120428^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 26430227 + ... + 26431026.

Almost surely, 2^21144501200 is an apocalyptic number.

21144501200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21144501200 is an abundant number, since it is smaller than the sum of its proper divisors (29655163894).

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

21144501200 is a wasteful number, since it uses less digits than its factorization.

21144501200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52861271 (or 52861260 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The spelling of 21144501200 in words is "twenty-one billion, one hundred forty-four million, five hundred one thousand, two hundred".