21172650204 has 96 divisors (see below), whose sum is σ = 53102117376. Its totient is φ = 6542448640.

The previous prime is 21172650179. The next prime is 21172650217. The reversal of 21172650204 is 40205627112.

It is a super-2 number, since 2×21172650204² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3658297 + ... + 3664079.

It is an arithmetic number, because the mean of its divisors is an integer number (553147056).

Almost surely, 2^21172650204 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21172650204, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26551058688).

21172650204 is an abundant number, since it is smaller than the sum of its proper divisors (31929467172).

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

21172650204 is a wasteful number, since it uses less digits than its factorization.

21172650204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6075 (or 6073 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 30.

The spelling of 21172650204 in words is "twenty-one billion, one hundred seventy-two million, six hundred fifty thousand, two hundred four".