2156213940 has 48 divisors (see below), whose sum is σ = 6049030848. Its totient is φ = 573882624.

The previous prime is 2156213933. The next prime is 2156213951. The reversal of 2156213940 is 493126512.

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, 2977 + ... + 65736.

It is an arithmetic number, because the mean of its divisors is an integer number (126021476).

Almost surely, 2^2156213940 is an apocalyptic number.

2156213940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2156213940 is an abundant number, since it is smaller than the sum of its proper divisors (3892816908).

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

2156213940 is a wasteful number, since it uses less digits than its factorization.

2156213940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69248 (or 69246 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 2156213940 is about 46435.0507698656. The cubic root of 2156213940 is about 1291.9051112949.

The spelling of 2156213940 in words is "two billion, one hundred fifty-six million, two hundred thirteen thousand, nine hundred forty".