161310440 has 32 divisors (see below), whose sum is σ = 363557160. Its totient is φ = 64416000.

The previous prime is 161310427. The next prime is 161310451. The reversal of 161310440 is 44013161.

It can be written as a sum of positive squares in 4 ways, for example, as 152226244 + 9084196 = 12338^2 + 3014^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23390 + ... + 29490.

Almost surely, 2^161310440 is an apocalyptic number.

161310440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161310440 is an abundant number, since it is smaller than the sum of its proper divisors (202246720).

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

161310440 is a wasteful number, since it uses less digits than its factorization.

161310440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6773 (or 6769 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 161310440 is about 12700.8046989157. The cubic root of 161310440 is about 544.3616125856.

The spelling of 161310440 in words is "one hundred sixty-one million, three hundred ten thousand, four hundred forty".