161898490 has 64 divisors (see below), whose sum is σ = 322672896. Its totient is φ = 58125312.

The previous prime is 161898481. The next prime is 161898493. The reversal of 161898490 is 94898161.

It is a super-2 number, since 2×161898490² = 52422242128560200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 161898490.

It is not an unprimeable number, because it can be changed into a prime (161898493) 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, 1432674 + ... + 1432786.

It is an arithmetic number, because the mean of its divisors is an integer number (5041764).

Almost surely, 2^161898490 is an apocalyptic number.

161898490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161898490 is a deficient number, since it is larger than the sum of its proper divisors (160774406).

161898490 is a wasteful number, since it uses less digits than its factorization.

161898490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343.

The product of its (nonzero) digits is 124416, while the sum is 46.

The square root of 161898490 is about 12723.9337470768. The cubic root of 161898490 is about 545.0222923856.

The spelling of 161898490 in words is "one hundred sixty-one million, eight hundred ninety-eight thousand, four hundred ninety".