161549513 has 4 divisors (see below), whose sum is σ = 161686800. Its totient is φ = 161412228.

The previous prime is 161549503. The next prime is 161549537. The reversal of 161549513 is 315945161.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161549513 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161549503) 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 3 ways as a sum of consecutive naturals, for example, 66863 + ... + 69236.

It is an arithmetic number, because the mean of its divisors is an integer number (40421700).

Almost surely, 2^161549513 is an apocalyptic number.

It is an amenable number.

161549513 is a deficient number, since it is larger than the sum of its proper divisors (137287).

161549513 is a wasteful number, since it uses less digits than its factorization.

161549513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137286.

The product of its digits is 16200, while the sum is 35.

The square root of 161549513 is about 12710.2129407811. The cubic root of 161549513 is about 544.6304067681.

The spelling of 161549513 in words is "one hundred sixty-one million, five hundred forty-nine thousand, five hundred thirteen".