31213121012189 has 2 divisors, whose sum is σ = 31213121012190. Its totient is φ = 31213121012188.

The previous prime is 31213121012179. The next prime is 31213121012239. The reversal of 31213121012189 is 98121012131213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17959516709689 + 13253604302500 = 4237867^2 + 3640550^2 .

It is an emirp because it is prime and its reverse (98121012131213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31213121012189 - 2⁴ = 31213121012173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31213121012179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15606560506094 + 15606560506095.

It is an arithmetic number, because the mean of its divisors is an integer number (15606560506095).

Almost surely, 2^{31213121012189} is an apocalyptic number.

It is an amenable number.

31213121012189 is a deficient number, since it is larger than the sum of its proper divisors (1).

31213121012189 is an equidigital number, since it uses as much as digits as its factorization.

31213121012189 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 35.

The spelling of 31213121012189 in words is "thirty-one trillion, two hundred thirteen billion, one hundred twenty-one million, twelve thousand, one hundred eighty-nine".