21293773172 has 24 divisors (see below), whose sum is σ = 43100654016. Its totient is φ = 9015951168.

The previous prime is 21293773169. The next prime is 21293773187. The reversal of 21293773172 is 27137739212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4578953 + ... + 4583600.

It is an arithmetic number, because the mean of its divisors is an integer number (1795860584).

Almost surely, 2^21293773172 is an apocalyptic number.

It is an amenable number.

21293773172 is an abundant number, since it is smaller than the sum of its proper divisors (21806880844).

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

21293773172 is a wasteful number, since it uses less digits than its factorization.

21293773172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9162647 (or 9162645 counting only the distinct ones).

The product of its digits is 222264, while the sum is 44.

The spelling of 21293773172 in words is "twenty-one billion, two hundred ninety-three million, seven hundred seventy-three thousand, one hundred seventy-two".