8161890 has 32 divisors (see below), whose sum is σ = 21370176. Its totient is φ = 1978560.

The previous prime is 8161889. The next prime is 8161903. The reversal of 8161890 is 981618.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12037 + ... + 12696.

It is an arithmetic number, because the mean of its divisors is an integer number (667818).

Almost surely, 2^8161890 is an apocalyptic number.

8161890 is an abundant number, since it is smaller than the sum of its proper divisors (13208286).

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

8161890 is a wasteful number, since it uses less digits than its factorization.

8161890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24754.

The product of its (nonzero) digits is 3456, while the sum is 33.

The square root of 8161890 is about 2856.9021684335. The cubic root of 8161890 is about 201.3400841510.

The spelling of 8161890 in words is "eight million, one hundred sixty-one thousand, eight hundred ninety".