161567431177 has 4 divisors (see below), whose sum is σ = 161568240336. Its totient is φ = 161566622020.

The previous prime is 161567431169. The next prime is 161567431241. The reversal of 161567431177 is 771134765161.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 161567431177 - 2³ = 161567431169 is a prime.

It is a super-2 number, since 2×161567431177² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161567431177.

It is not an unprimeable number, because it can be changed into a prime (161567431147) 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, 133278 + ... + 583864.

It is an arithmetic number, because the mean of its divisors is an integer number (40392060084).

Almost surely, 2^161567431177 is an apocalyptic number.

It is an amenable number.

161567431177 is a deficient number, since it is larger than the sum of its proper divisors (809159).

161567431177 is an equidigital number, since it uses as much as digits as its factorization.

161567431177 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 809158.

The product of its digits is 740880, while the sum is 49.

The spelling of 161567431177 in words is "one hundred sixty-one billion, five hundred sixty-seven million, four hundred thirty-one thousand, one hundred seventy-seven".