161136540 has 120 divisors (see below), whose sum is σ = 535317552. Its totient is φ = 40435200.

The previous prime is 161136533. The next prime is 161136571. The reversal of 161136540 is 45631161.

161136540 is a `hidden beast` number, since 1 + 6 + 1 + 1 + 3 + 654 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 24615 + ... + 30465.

Almost surely, 2^161136540 is an apocalyptic number.

161136540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161136540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (267658776).

161136540 is an abundant number, since it is smaller than the sum of its proper divisors (374181012).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161136540 is a wasteful number, since it uses less digits than its factorization.

161136540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5889 (or 5878 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 161136540 is about 12693.9568299250. The cubic root of 161136540 is about 544.1659267136.

The spelling of 161136540 in words is "one hundred sixty-one million, one hundred thirty-six thousand, five hundred forty".