3118689781 has 4 divisors (see below), whose sum is σ = 3202978732. Its totient is φ = 3034400832.

The previous prime is 3118689751. The next prime is 3118689799. The reversal of 3118689781 is 1879868113.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2355549156 + 763140625 = 48534^2 + 27625^2 .

It is a cyclic number.

It is not a de Polignac number, because 3118689781 - 2¹³ = 3118681589 is a prime.

It is a super-2 number, since 2×3118689781² = 19452451900227655922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3118689751) 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, 42144420 + ... + 42144493.

It is an arithmetic number, because the mean of its divisors is an integer number (800744683).

Almost surely, 2^3118689781 is an apocalyptic number.

It is an amenable number.

3118689781 is a deficient number, since it is larger than the sum of its proper divisors (84288951).

3118689781 is an equidigital number, since it uses as much as digits as its factorization.

3118689781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84288950.

The product of its digits is 580608, while the sum is 52.

The square root of 3118689781 is about 55845.2306020845. The cubic root of 3118689781 is about 1461.0241424103.

The spelling of 3118689781 in words is "three billion, one hundred eighteen million, six hundred eighty-nine thousand, seven hundred eighty-one".