21201588044 has 48 divisors (see below), whose sum is σ = 45707225088. Its totient is φ = 8379678528.

The previous prime is 21201588043. The next prime is 21201588061. The reversal of 21201588044 is 44088510212.

It is a junction number, because it is equal to n+sod(n) for n = 21201587995 and 21201588013.

It is not an unprimeable number, because it can be changed into a prime (21201588043) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 375089 + ... + 427895.

It is an arithmetic number, because the mean of its divisors is an integer number (952233856).

Almost surely, 2^21201588044 is an apocalyptic number.

It is an amenable number.

21201588044 is an abundant number, since it is smaller than the sum of its proper divisors (24505637044).

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

21201588044 is a wasteful number, since it uses less digits than its factorization.

21201588044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53934 (or 53932 counting only the distinct ones).

The product of its (nonzero) digits is 20480, while the sum is 35.

The spelling of 21201588044 in words is "twenty-one billion, two hundred one million, five hundred eighty-eight thousand, forty-four".