161151111 has 24 divisors (see below), whose sum is σ = 258734736. Its totient is φ = 95821440.

The previous prime is 161151097. The next prime is 161151119. The reversal of 161151111 is 111151161.

It is a happy number.

161151111 is a `hidden beast` number, since 1 + 611 + 51 + 1 + 1 + 1 = 666.

It is not a de Polignac number, because 161151111 - 2¹⁵ = 161118343 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161151119) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10110 + ... + 20603.

It is an arithmetic number, because the mean of its divisors is an integer number (10780614).

Almost surely, 2^161151111 is an apocalyptic number.

161151111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

161151111 is a deficient number, since it is larger than the sum of its proper divisors (97583625).

161151111 is a wasteful number, since it uses less digits than its factorization.

161151111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30783 (or 30780 counting only the distinct ones).

The product of its digits is 30, while the sum is 18.

The square root of 161151111 is about 12694.5307514693. The cubic root of 161151111 is about 544.1823285443.

The spelling of 161151111 in words is "one hundred sixty-one million, one hundred fifty-one thousand, one hundred eleven".