1909190138 has 4 divisors (see below), whose sum is σ = 2863785210. Its totient is φ = 954595068.

The previous prime is 1909190123. The next prime is 1909190177. The reversal of 1909190138 is 8310919091.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1800050329 + 109139809 = 42427^2 + 10447^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1909190095 and 1909190104.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 477297533 + ... + 477297536.

Almost surely, 2^1909190138 is an apocalyptic number.

1909190138 is a deficient number, since it is larger than the sum of its proper divisors (954595072).

1909190138 is an equidigital number, since it uses as much as digits as its factorization.

1909190138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 954595071.

The product of its (nonzero) digits is 17496, while the sum is 41.

The square root of 1909190138 is about 43694.2803808462. The cubic root of 1909190138 is about 1240.5560587061.

The spelling of 1909190138 in words is "one billion, nine hundred nine million, one hundred ninety thousand, one hundred thirty-eight".