166403890 has 16 divisors (see below), whose sum is σ = 300202200. Its totient is φ = 66411520.

The previous prime is 166403857. The next prime is 166403917. The reversal of 166403890 is 98304661.

It can be written as a sum of positive squares in 4 ways, for example, as 161264601 + 5139289 = 12699^2 + 2267^2 .

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, 14041 + ... + 23020.

Almost surely, 2^166403890 is an apocalyptic number.

166403890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

166403890 is a deficient number, since it is larger than the sum of its proper divisors (133798310).

166403890 is a wasteful number, since it uses less digits than its factorization.

166403890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37517.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 166403890 is about 12899.7631761207. The cubic root of 166403890 is about 550.0318328683.

The spelling of 166403890 in words is "one hundred sixty-six million, four hundred three thousand, eight hundred ninety".