161505644 has 24 divisors (see below), whose sum is σ = 303735600. Its totient is φ = 74866176.

The previous prime is 161505623. The next prime is 161505647. The reversal of 161505644 is 446505161.

It is a self number, because there is not a number n which added to its sum of digits gives 161505644.

It is not an unprimeable number, because it can be changed into a prime (161505647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13169 + ... + 22280.

It is an arithmetic number, because the mean of its divisors is an integer number (12655650).

Almost surely, 2^161505644 is an apocalyptic number.

It is an amenable number.

161505644 is a deficient number, since it is larger than the sum of its proper divisors (142229956).

161505644 is a wasteful number, since it uses less digits than its factorization.

161505644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35537 (or 35535 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 161505644 is about 12708.4870854087. The cubic root of 161505644 is about 544.5811039179.

The spelling of 161505644 in words is "one hundred sixty-one million, five hundred five thousand, six hundred forty-four".