161650040 has 64 divisors (see below), whose sum is σ = 375926400. Its totient is φ = 62512128.

The previous prime is 161650039. The next prime is 161650051. The reversal of 161650040 is 40056161.

It is a super-2 number, since 2×161650040² = 52261470864003200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161649988 and 161650015.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 353492 + ... + 353948.

It is an arithmetic number, because the mean of its divisors is an integer number (5873850).

Almost surely, 2^161650040 is an apocalyptic number.

161650040 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 161650040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187963200).

161650040 is an abundant number, since it is smaller than the sum of its proper divisors (214276360).

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

161650040 is a wasteful number, since it uses less digits than its factorization.

161650040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 744 (or 740 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 161650040 is about 12714.1669015315. The cubic root of 161650040 is about 544.7433519315.

The spelling of 161650040 in words is "one hundred sixty-one million, six hundred fifty thousand, forty".