20111972120 has 64 divisors (see below), whose sum is σ = 46906776000. Its totient is φ = 7751715328.

The previous prime is 20111972117. The next prime is 20111972189. The reversal of 20111972120 is 2127911102.

It is a self number, because there is not a number n which added to its sum of digits gives 20111972120.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 566246 + ... + 600714.

It is an arithmetic number, because the mean of its divisors is an integer number (732918375).

Almost surely, 2^20111972120 is an apocalyptic number.

20111972120 is a gapful number since it is divisible by the number (20) 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 20111972120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23453388000).

20111972120 is an abundant number, since it is smaller than the sum of its proper divisors (26794803880).

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

20111972120 is a wasteful number, since it uses less digits than its factorization.

20111972120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35012 (or 35008 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 26.

The spelling of 20111972120 in words is "twenty billion, one hundred eleven million, nine hundred seventy-two thousand, one hundred twenty".