2157640770 has 16 divisors (see below), whose sum is σ = 5178337920. Its totient is φ = 575370864.

The previous prime is 2157640757. The next prime is 2157640777. The reversal of 2157640770 is 770467512.

It is not an unprimeable number, because it can be changed into a prime (2157640777) by changing a digit.

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, 35960650 + ... + 35960709.

It is an arithmetic number, because the mean of its divisors is an integer number (323646120).

Almost surely, 2^2157640770 is an apocalyptic number.

2157640770 is an abundant number, since it is smaller than the sum of its proper divisors (3020697150).

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

2157640770 is a wasteful number, since it uses less digits than its factorization.

2157640770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71921369.

The product of its (nonzero) digits is 82320, while the sum is 39.

The square root of 2157640770 is about 46450.4119465048. The cubic root of 2157640770 is about 1292.1900122951.

The spelling of 2157640770 in words is "two billion, one hundred fifty-seven million, six hundred forty thousand, seven hundred seventy".