161788490 has 16 divisors (see below), whose sum is σ = 308350152. Its totient is φ = 60908544.

The previous prime is 161788483. The next prime is 161788499. The reversal of 161788490 is 94887161.

It can be written as a sum of positive squares in 4 ways, for example, as 106151809 + 55636681 = 10303^2 + 7459^2 .

It is not an unprimeable number, because it can be changed into a prime (161788499) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 475679 + ... + 476018.

Almost surely, 2^161788490 is an apocalyptic number.

161788490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161788490 is a deficient number, since it is larger than the sum of its proper divisors (146561662).

161788490 is a wasteful number, since it uses less digits than its factorization.

161788490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 951721.

The product of its (nonzero) digits is 96768, while the sum is 44.

The square root of 161788490 is about 12719.6104500099. The cubic root of 161788490 is about 544.8988281184.

The spelling of 161788490 in words is "one hundred sixty-one million, seven hundred eighty-eight thousand, four hundred ninety".