161477509291 has 16 divisors (see below), whose sum is σ = 186207081984. Its totient is φ = 137163648384.

The previous prime is 161477509243. The next prime is 161477509309. The reversal of 161477509291 is 192905774161.

It is a de Polignac number, because none of the positive numbers 2^k-161477509291 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161477509201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7540986 + ... + 7562368.

It is an arithmetic number, because the mean of its divisors is an integer number (11637942624).

Almost surely, 2^161477509291 is an apocalyptic number.

161477509291 is a deficient number, since it is larger than the sum of its proper divisors (24729572693).

161477509291 is a wasteful number, since it uses less digits than its factorization.

161477509291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31050.

The product of its (nonzero) digits is 952560, while the sum is 52.

The spelling of 161477509291 in words is "one hundred sixty-one billion, four hundred seventy-seven million, five hundred nine thousand, two hundred ninety-one".