161617513 has 4 divisors (see below), whose sum is σ = 163893888. Its totient is φ = 159341140.

The previous prime is 161617507. The next prime is 161617523. The reversal of 161617513 is 315716161.

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 not a de Polignac number, because 161617513 - 2¹³ = 161609321 is a prime.

It is a super-2 number, since 2×161617513² = 52240441016610338, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161617523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1138081 + ... + 1138222.

It is an arithmetic number, because the mean of its divisors is an integer number (40973472).

Almost surely, 2^161617513 is an apocalyptic number.

It is an amenable number.

161617513 is a deficient number, since it is larger than the sum of its proper divisors (2276375).

161617513 is an equidigital number, since it uses as much as digits as its factorization.

161617513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2276374.

The product of its digits is 3780, while the sum is 31.

The square root of 161617513 is about 12712.8876735382. The cubic root of 161617513 is about 544.7068119764.

The spelling of 161617513 in words is "one hundred sixty-one million, six hundred seventeen thousand, five hundred thirteen".