161277992 has 8 divisors (see below), whose sum is σ = 302396250. Its totient is φ = 80638992.

The previous prime is 161277979. The next prime is 161278003. The reversal of 161277992 is 299772161.

It can be written as a sum of positive squares in only one way, i.e., 160934596 + 343396 = 12686^2 + 586^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10079867 + ... + 10079882.

Almost surely, 2^161277992 is an apocalyptic number.

It is an amenable number.

161277992 is a deficient number, since it is larger than the sum of its proper divisors (141118258).

161277992 is a wasteful number, since it uses less digits than its factorization.

161277992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20159755 (or 20159751 counting only the distinct ones).

The product of its digits is 95256, while the sum is 44.

The square root of 161277992 is about 12699.5272352950. The cubic root of 161277992 is about 544.3251102363.

The spelling of 161277992 in words is "one hundred sixty-one million, two hundred seventy-seven thousand, nine hundred ninety-two".