161332890 has 32 divisors (see below), whose sum is σ = 409976640. Its totient is φ = 40491264.

The previous prime is 161332889. The next prime is 161332891. The reversal of 161332890 is 98233161.

It is an interprime number because it is at equal distance from previous prime (161332889) and next prime (161332891).

It is not an unprimeable number, because it can be changed into a prime (161332891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 157660 + ... + 158679.

It is an arithmetic number, because the mean of its divisors is an integer number (12811770).

Almost surely, 2^161332890 is an apocalyptic number.

161332890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161332890 is an abundant number, since it is smaller than the sum of its proper divisors (248643750).

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

161332890 is a wasteful number, since it uses less digits than its factorization.

161332890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316366.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 161332890 is about 12701.6884704357. The cubic root of 161332890 is about 544.3868648287.

The spelling of 161332890 in words is "one hundred sixty-one million, three hundred thirty-two thousand, eight hundred ninety".