161505515 has 4 divisors (see below), whose sum is σ = 193806624. Its totient is φ = 129204408.

The previous prime is 161505499. The next prime is 161505521. The reversal of 161505515 is 515505161.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 161505515 - 2⁴ = 161505499 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16150547 + ... + 16150556.

It is an arithmetic number, because the mean of its divisors is an integer number (48451656).

Almost surely, 2^161505515 is an apocalyptic number.

161505515 is a deficient number, since it is larger than the sum of its proper divisors (32301109).

161505515 is an equidigital number, since it uses as much as digits as its factorization.

161505515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32301108.

The product of its (nonzero) digits is 3750, while the sum is 29.

The square root of 161505515 is about 12708.4820100593. The cubic root of 161505515 is about 544.5809589261.

The spelling of 161505515 in words is "one hundred sixty-one million, five hundred five thousand, five hundred fifteen".