131661643279 has 4 divisors (see below), whose sum is σ = 137386062576. Its totient is φ = 125937223984.

The previous prime is 131661643277. The next prime is 131661643291. The reversal of 131661643279 is 972346166131.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 131661643279 - 2¹ = 131661643277 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131661643277) 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, 2862209614 + ... + 2862209659.

It is an arithmetic number, because the mean of its divisors is an integer number (34346515644).

Almost surely, 2^131661643279 is an apocalyptic number.

131661643279 is a deficient number, since it is larger than the sum of its proper divisors (5724419297).

131661643279 is an equidigital number, since it uses as much as digits as its factorization.

131661643279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5724419296.

The product of its digits is 979776, while the sum is 49.

The spelling of 131661643279 in words is "one hundred thirty-one billion, six hundred sixty-one million, six hundred forty-three thousand, two hundred seventy-nine".