2161306957 has 4 divisors (see below), whose sum is σ = 2163659680. Its totient is φ = 2158954236.

The previous prime is 2161306933. The next prime is 2161306963. The reversal of 2161306957 is 7596031612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2161306957 - 2³¹ = 13823309 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161306967) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1174983 + ... + 1176820.

It is an arithmetic number, because the mean of its divisors is an integer number (540914920).

Almost surely, 2^2161306957 is an apocalyptic number.

It is an amenable number.

2161306957 is a deficient number, since it is larger than the sum of its proper divisors (2352723).

2161306957 is an equidigital number, since it uses as much as digits as its factorization.

2161306957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2352722.

The product of its (nonzero) digits is 68040, while the sum is 40.

The square root of 2161306957 is about 46489.8586468060. The cubic root of 2161306957 is about 1292.9214793690.

The spelling of 2161306957 in words is "two billion, one hundred sixty-one million, three hundred six thousand, nine hundred fifty-seven".