31020012209 has 4 divisors (see below), whose sum is σ = 32368708416. Its totient is φ = 29671316004.

The previous prime is 31020012169. The next prime is 31020012211. The reversal of 31020012209 is 90221002013.

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 a de Polignac number, because none of the positive numbers 2^k-31020012209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31020012229) 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, 674348069 + ... + 674348114.

It is an arithmetic number, because the mean of its divisors is an integer number (8092177104).

Almost surely, 2^31020012209 is an apocalyptic number.

It is an amenable number.

31020012209 is a deficient number, since it is larger than the sum of its proper divisors (1348696207).

31020012209 is a wasteful number, since it uses less digits than its factorization.

31020012209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1348696206.

The product of its (nonzero) digits is 216, while the sum is 20.

The spelling of 31020012209 in words is "thirty-one billion, twenty million, twelve thousand, two hundred nine".