1909993101 has 4 divisors (see below), whose sum is σ = 2546657472. Its totient is φ = 1273328732.

The previous prime is 1909993093. The next prime is 1909993139. The reversal of 1909993101 is 1013999091.

1909993101 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1909993101 - 2³ = 1909993093 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1909993181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 318332181 + ... + 318332186.

It is an arithmetic number, because the mean of its divisors is an integer number (636664368).

Almost surely, 2^1909993101 is an apocalyptic number.

1909993101 is the 27641-st centered pentagonal number.

It is an amenable number.

1909993101 is a deficient number, since it is larger than the sum of its proper divisors (636664371).

1909993101 is an equidigital number, since it uses as much as digits as its factorization.

1909993101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 636664370.

The product of its (nonzero) digits is 19683, while the sum is 42.

The square root of 1909993101 is about 43703.4678372323. The cubic root of 1909993101 is about 1240.7299511118.

The spelling of 1909993101 in words is "one billion, nine hundred nine million, nine hundred ninety-three thousand, one hundred one".