1956438109 has 4 divisors (see below), whose sum is σ = 1960423200. Its totient is φ = 1952453020.

The previous prime is 1956438101. The next prime is 1956438137. The reversal of 1956438109 is 9018346591.

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 1956438109 - 2³ = 1956438101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1956438101) 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, 1991809 + ... + 1992790.

It is an arithmetic number, because the mean of its divisors is an integer number (490105800).

Almost surely, 2^1956438109 is an apocalyptic number.

It is an amenable number.

1956438109 is a deficient number, since it is larger than the sum of its proper divisors (3985091).

1956438109 is an equidigital number, since it uses as much as digits as its factorization.

1956438109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3985090.

The product of its (nonzero) digits is 233280, while the sum is 46.

The square root of 1956438109 is about 44231.6414911317. The cubic root of 1956438109 is about 1250.7063973137.

The spelling of 1956438109 in words is "one billion, nine hundred fifty-six million, four hundred thirty-eight thousand, one hundred nine".