161640090 has 64 divisors (see below), whose sum is σ = 449798400. Its totient is φ = 41228352.

The previous prime is 161640071. The next prime is 161640103. The reversal of 161640090 is 90046161.

161640090 is a `hidden beast` number, since 1 + 616 + 40 + 0 + 9 + 0 = 666.

161640090 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×161640090² = 52255037390416200, which contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6805 + ... + 19224.

It is an arithmetic number, because the mean of its divisors is an integer number (7028100).

Almost surely, 2^161640090 is an apocalyptic number.

161640090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161640090 is an abundant number, since it is smaller than the sum of its proper divisors (288158310).

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

161640090 is a wasteful number, since it uses less digits than its factorization.

161640090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26068 (or 26062 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 161640090 is about 12713.7755997186. The cubic root of 161640090 is about 544.7321748901.

The spelling of 161640090 in words is "one hundred sixty-one million, six hundred forty thousand, ninety".