161942840 has 32 divisors (see below), whose sum is σ = 364782960. Its totient is φ = 64704000.

The previous prime is 161942827. The next prime is 161942843. The reversal of 161942840 is 48249161.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 161942840.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161942843) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 46355 + ... + 49725.

Almost surely, 2^161942840 is an apocalyptic number.

161942840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161942840 is an abundant number, since it is smaller than the sum of its proper divisors (202840120).

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

161942840 is a wasteful number, since it uses less digits than its factorization.

161942840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4583 (or 4579 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 161942840 is about 12725.6764063841. The cubic root of 161942840 is about 545.0720551141.

The spelling of 161942840 in words is "one hundred sixty-one million, nine hundred forty-two thousand, eight hundred forty".