3121878889 has 4 divisors (see below), whose sum is σ = 3122182224. Its totient is φ = 3121575556.

The previous prime is 3121878887. The next prime is 3121878931. The reversal of 3121878889 is 9888781213.

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 3121878889 - 2¹ = 3121878887 is a prime.

It is a super-2 number, since 2×3121878889² = 19492255595167748642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3121878883) 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, 135667 + ... + 157000.

It is an arithmetic number, because the mean of its divisors is an integer number (780545556).

Almost surely, 2^3121878889 is an apocalyptic number.

It is an amenable number.

3121878889 is a deficient number, since it is larger than the sum of its proper divisors (303335).

3121878889 is a wasteful number, since it uses less digits than its factorization.

3121878889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303334.

The product of its digits is 1548288, while the sum is 55.

The square root of 3121878889 is about 55873.7763982353. The cubic root of 3121878889 is about 1461.5219771657.

The spelling of 3121878889 in words is "three billion, one hundred twenty-one million, eight hundred seventy-eight thousand, eight hundred eighty-nine".