161223515 has 8 divisors (see below), whose sum is σ = 194471808. Its totient is φ = 128309760.

The previous prime is 161223511. The next prime is 161223523. The reversal of 161223515 is 515322161.

161223515 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 161223515 - 2² = 161223511 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161223511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82571 + ... + 84500.

It is an arithmetic number, because the mean of its divisors is an integer number (24308976).

Almost surely, 2^161223515 is an apocalyptic number.

161223515 is a deficient number, since it is larger than the sum of its proper divisors (33248293).

161223515 is a wasteful number, since it uses less digits than its factorization.

161223515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167269.

The product of its digits is 1800, while the sum is 26.

The square root of 161223515 is about 12697.3822105188. The cubic root of 161223515 is about 544.2638153709.

Adding to 161223515 its reverse (515322161), we get a palindrome (676545676).

The spelling of 161223515 in words is "one hundred sixty-one million, two hundred twenty-three thousand, five hundred fifteen".