161129578 has 4 divisors (see below), whose sum is σ = 241694370. Its totient is φ = 80564788.

The previous prime is 161129567. The next prime is 161129581. The reversal of 161129578 is 875921161.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 122478489 + 38651089 = 11067^2 + 6217^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 161129578.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40282393 + ... + 40282396.

Almost surely, 2^161129578 is an apocalyptic number.

161129578 is a deficient number, since it is larger than the sum of its proper divisors (80564792).

161129578 is an equidigital number, since it uses as much as digits as its factorization.

161129578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80564791.

The product of its digits is 30240, while the sum is 40.

The square root of 161129578 is about 12693.6826019875. The cubic root of 161129578 is about 544.1580895966.

The spelling of 161129578 in words is "one hundred sixty-one million, one hundred twenty-nine thousand, five hundred seventy-eight".