31209223139 has 2 divisors, whose sum is σ = 31209223140. Its totient is φ = 31209223138.

The previous prime is 31209223117. The next prime is 31209223153. The reversal of 31209223139 is 93132290213.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (93132290213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31209223139 - 2²⁰ = 31208174563 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31209223099 and 31209223108.

It is not a weakly prime, because it can be changed into another prime (31209223159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15604611569 + 15604611570.

It is an arithmetic number, because the mean of its divisors is an integer number (15604611570).

Almost surely, 2^31209223139 is an apocalyptic number.

31209223139 is a deficient number, since it is larger than the sum of its proper divisors (1).

31209223139 is an equidigital number, since it uses as much as digits as its factorization.

31209223139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17496, while the sum is 35.

The spelling of 31209223139 in words is "thirty-one billion, two hundred nine million, two hundred twenty-three thousand, one hundred thirty-nine".