100661090 has 32 divisors (see below), whose sum is σ = 187167024. Its totient is φ = 38949120.

The previous prime is 100661083. The next prime is 100661101. The reversal of 100661090 is 90166001.

It is a Cunningham number, because it is equal to 10033²+1.

It can be written as a sum of positive squares in 8 ways, for example, as 90079081 + 10582009 = 9491^2 + 3253^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72200 + ... + 73580.

Almost surely, 2^100661090 is an apocalyptic number.

100661090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

100661090 is a deficient number, since it is larger than the sum of its proper divisors (86505934).

100661090 is a wasteful number, since it uses less digits than its factorization.

100661090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1622.

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 100661090 is about 10033.0000498355. Note that the first 4 decimals coincide. The cubic root of 100661090 is about 465.1794736350.

The spelling of 100661090 in words is "one hundred million, six hundred sixty-one thousand, ninety".