161111363505 has 32 divisors (see below), whose sum is σ = 259626052224. Its totient is φ = 85312290816.

The previous prime is 161111363489. The next prime is 161111363509. The reversal of 161111363505 is 505363111161.

It is not a de Polignac number, because 161111363505 - 2⁴ = 161111363489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161111363509) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1115419 + ... + 1251551.

It is an arithmetic number, because the mean of its divisors is an integer number (8113314132).

Almost surely, 2^161111363505 is an apocalyptic number.

161111363505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161111363505 is a deficient number, since it is larger than the sum of its proper divisors (98514688719).

161111363505 is a wasteful number, since it uses less digits than its factorization.

161111363505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136705.

The product of its (nonzero) digits is 8100, while the sum is 33.

Adding to 161111363505 its reverse (505363111161), we get a palindrome (666474474666).

The spelling of 161111363505 in words is "one hundred sixty-one billion, one hundred eleven million, three hundred sixty-three thousand, five hundred five".