161906442 has 16 divisors (see below), whose sum is σ = 323988672. Its totient is φ = 53939520.

The previous prime is 161906431. The next prime is 161906447. The reversal of 161906442 is 244609161.

It is a super-2 number, since 2×161906442² = 52427391922198728, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161906447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6723 + ... + 19209.

It is an arithmetic number, because the mean of its divisors is an integer number (20249292).

Almost surely, 2^161906442 is an apocalyptic number.

161906442 is an abundant number, since it is smaller than the sum of its proper divisors (162082230).

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

161906442 is a wasteful number, since it uses less digits than its factorization.

161906442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14653.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 161906442 is about 12724.2462252190. The cubic root of 161906442 is about 545.0312155619.

The spelling of 161906442 in words is "one hundred sixty-one million, nine hundred six thousand, four hundred forty-two".