123991090 has 8 divisors (see below), whose sum is σ = 223183980. Its totient is φ = 49596432.

The previous prime is 123991079. The next prime is 123991117. The reversal of 123991090 is 90199321.

It can be written as a sum of positive squares in 2 ways, for example, as 115412049 + 8579041 = 10743^2 + 2929^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6199545 + ... + 6199564.

Almost surely, 2^123991090 is an apocalyptic number.

123991090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

123991090 is a deficient number, since it is larger than the sum of its proper divisors (99192890).

123991090 is a wasteful number, since it uses less digits than its factorization.

123991090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12399116.

The product of its (nonzero) digits is 4374, while the sum is 34.

The square root of 123991090 is about 11135.1286476628. The cubic root of 123991090 is about 498.6511511524.

It can be divided in two parts, 1239 and 91090, that added together give a palindrome (92329).

The spelling of 123991090 in words is "one hundred twenty-three million, nine hundred ninety-one thousand, ninety".