161555115 has 16 divisors (see below), whose sum is σ = 258697728. Its totient is φ = 86092896.

The previous prime is 161555111. The next prime is 161555117. The reversal of 161555115 is 511555161.

It is not a de Polignac number, because 161555115 - 2² = 161555111 is a prime.

It is a super-2 number, since 2×161555115² = 52200110365326450, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161555111) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18684 + ... + 25926.

It is an arithmetic number, because the mean of its divisors is an integer number (16168608).

Almost surely, 2^161555115 is an apocalyptic number.

161555115 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

161555115 is a deficient number, since it is larger than the sum of its proper divisors (97142613).

161555115 is a wasteful number, since it uses less digits than its factorization.

161555115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8738.

The product of its digits is 3750, while the sum is 30.

The square root of 161555115 is about 12710.4333128340. The cubic root of 161555115 is about 544.6367020192.

The spelling of 161555115 in words is "one hundred sixty-one million, five hundred fifty-five thousand, one hundred fifteen".