2131945920 has 784 divisors, whose sum is σ = 8861694240. Its totient is φ = 483729408.

The previous prime is 2131945859. The next prime is 2131945927. The reversal of 2131945920 is 295491312.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2131945927) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 57620142 + ... + 57620178.

Almost surely, 2^2131945920 is an apocalyptic number.

2131945920 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 2131945920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4430847120).

2131945920 is an abundant number, since it is smaller than the sum of its proper divisors (6729748320).

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

2131945920 is a wasteful number, since it uses less digits than its factorization.

2131945920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104 (or 79 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 2131945920 is about 46172.9999025404. Note that the first 4 decimals coincide. The cubic root of 2131945920 is about 1287.0400496119.

The spelling of 2131945920 in words is "two billion, one hundred thirty-one million, nine hundred forty-five thousand, nine hundred twenty".