31985489 has 2 divisors, whose sum is σ = 31985490. Its totient is φ = 31985488.

The previous prime is 31985477. The next prime is 31985491. The reversal of 31985489 is 98458913.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29246464 + 2739025 = 5408^2 + 1655^2 .

It is a cyclic number.

It is not a de Polignac number, because 31985489 - 2²⁴ = 15208273 is a prime.

Together with 31985491, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31985089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15992744 + 15992745.

It is an arithmetic number, because the mean of its divisors is an integer number (15992745).

Almost surely, 2^31985489 is an apocalyptic number.

It is an amenable number.

31985489 is a deficient number, since it is larger than the sum of its proper divisors (1).

31985489 is an equidigital number, since it uses as much as digits as its factorization.

31985489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 47.

The square root of 31985489 is about 5655.5715007415. The cubic root of 31985489 is about 317.4322140199.

The spelling of 31985489 in words is "thirty-one million, nine hundred eighty-five thousand, four hundred eighty-nine".