2171880156 has 24 divisors (see below), whose sum is σ = 5288056704. Its totient is φ = 692483440.

The previous prime is 2171880127. The next prime is 2171880223. The reversal of 2171880156 is 6510881712.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3934290 + ... + 3934841.

It is an arithmetic number, because the mean of its divisors is an integer number (220335696).

Almost surely, 2^2171880156 is an apocalyptic number.

It is an amenable number.

2171880156 is an abundant number, since it is smaller than the sum of its proper divisors (3116176548).

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

2171880156 is a wasteful number, since it uses less digits than its factorization.

2171880156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7869161 (or 7869159 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 39.

The square root of 2171880156 is about 46603.4350236117. The cubic root of 2171880156 is about 1295.0263916348.

The spelling of 2171880156 in words is "two billion, one hundred seventy-one million, eight hundred eighty thousand, one hundred fifty-six".