1909813431 has 4 divisors (see below), whose sum is σ = 2546417912. Its totient is φ = 1273208952.

The previous prime is 1909813403. The next prime is 1909813447. The reversal of 1909813431 is 1343189091.

It is a happy number.

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

It is not a de Polignac number, because 1909813431 - 2¹⁰ = 1909812407 is a prime.

It is a super-2 number, since 2×1909813431² = 7294774682455983522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1909813431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1909813231) 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, 318302236 + ... + 318302241.

It is an arithmetic number, because the mean of its divisors is an integer number (636604478).

Almost surely, 2^1909813431 is an apocalyptic number.

1909813431 is a deficient number, since it is larger than the sum of its proper divisors (636604481).

1909813431 is an equidigital number, since it uses as much as digits as its factorization.

1909813431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 636604480.

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 1909813431 is about 43701.4122311854. The cubic root of 1909813431 is about 1240.6910453970.

The spelling of 1909813431 in words is "one billion, nine hundred nine million, eight hundred thirteen thousand, four hundred thirty-one".