2161377703609 has 2 divisors, whose sum is σ = 2161377703610. Its totient is φ = 2161377703608.

The previous prime is 2161377703601. The next prime is 2161377703621. The reversal of 2161377703609 is 9063077731612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1230885959209 + 930491744400 = 1109453^2 + 964620^2 .

It is a cyclic number.

It is not a de Polignac number, because 2161377703609 - 2³ = 2161377703601 is a prime.

It is a super-2 number, since 2×2161377703609² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2161377703601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1080688851804 + 1080688851805.

It is an arithmetic number, because the mean of its divisors is an integer number (1080688851805).

Almost surely, 2^{2161377703609} is an apocalyptic number.

It is an amenable number.

2161377703609 is a deficient number, since it is larger than the sum of its proper divisors (1).

2161377703609 is an equidigital number, since it uses as much as digits as its factorization.

2161377703609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2000376, while the sum is 52.

The spelling of 2161377703609 in words is "two trillion, one hundred sixty-one billion, three hundred seventy-seven million, seven hundred three thousand, six hundred nine".