161776440 has 240 divisors, whose sum is σ = 633144600. Its totient is φ = 36941184.

The previous prime is 161776421. The next prime is 161776451. The reversal of 161776440 is 44677161.

161776440 is a `hidden beast` number, since 1 + 6 + 1 + 7 + 7 + 644 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 161776395 and 161776404.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 158251 + ... + 159269.

Almost surely, 2^161776440 is an apocalyptic number.

161776440 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 161776440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (316572300).

161776440 is an abundant number, since it is smaller than the sum of its proper divisors (471368160).

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

161776440 is a wasteful number, since it uses less digits than its factorization.

161776440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1056 (or 1036 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 161776440 is about 12719.1367631612. The cubic root of 161776440 is about 544.8852997685.

The spelling of 161776440 in words is "one hundred sixty-one million, seven hundred seventy-six thousand, four hundred forty".