161897420 has 24 divisors (see below), whose sum is σ = 343166544. Its totient is φ = 64152896.

The previous prime is 161897419. The next prime is 161897447. The reversal of 161897420 is 24798161.

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, 35687 + ... + 39966.

It is an arithmetic number, because the mean of its divisors is an integer number (14298606).

Almost surely, 2^161897420 is an apocalyptic number.

161897420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161897420 is an abundant number, since it is smaller than the sum of its proper divisors (181269124).

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

161897420 is a wasteful number, since it uses less digits than its factorization.

161897420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75769 (or 75767 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 161897420 is about 12723.8917002621. The cubic root of 161897420 is about 545.0210916844.

The spelling of 161897420 in words is "one hundred sixty-one million, eight hundred ninety-seven thousand, four hundred twenty".