20015981172 has 144 divisors (see below), whose sum is σ = 58880908800. Its totient is φ = 5869670400.

The previous prime is 20015981159. The next prime is 20015981189. The reversal of 20015981172 is 27118951002.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 380404 + ... + 429812.

It is an arithmetic number, because the mean of its divisors is an integer number (408895200).

Almost surely, 2^20015981172 is an apocalyptic number.

20015981172 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20015981172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29440454400).

20015981172 is an abundant number, since it is smaller than the sum of its proper divisors (38864927628).

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

20015981172 is a wasteful number, since it uses less digits than its factorization.

20015981172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49475 (or 49456 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 36.

The spelling of 20015981172 in words is "twenty billion, fifteen million, nine hundred eighty-one thousand, one hundred seventy-two".