161391744 has 256 divisors, whose sum is σ = 524361600. Its totient is φ = 48660480.

The previous prime is 161391739. The next prime is 161391781. The reversal of 161391744 is 447193161.

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 = 161391699 and 161391708.

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 31 ways as a sum of consecutive naturals, for example, 2408799 + ... + 2408865.

Almost surely, 2^161391744 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161391744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (262180800).

161391744 is an abundant number, since it is smaller than the sum of its proper divisors (362969856).

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

161391744 is a wasteful number, since it uses less digits than its factorization.

161391744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148 (or 130 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 161391744 is about 12704.0050377824. The cubic root of 161391744 is about 544.4530539555.

The spelling of 161391744 in words is "one hundred sixty-one million, three hundred ninety-one thousand, seven hundred forty-four".