31404689 has 2 divisors, whose sum is σ = 31404690. Its totient is φ = 31404688.

The previous prime is 31404631. The next prime is 31404707. The reversal of 31404689 is 98640413.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26091664 + 5313025 = 5108^2 + 2305^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31404689 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (31404589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15702344 + 15702345.

It is an arithmetic number, because the mean of its divisors is an integer number (15702345).

Almost surely, 2^31404689 is an apocalyptic number.

It is an amenable number.

31404689 is a deficient number, since it is larger than the sum of its proper divisors (1).

31404689 is an equidigital number, since it uses as much as digits as its factorization.

31404689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 31404689 is about 5603.9886687965. The cubic root of 31404689 is about 315.4991297466.

The spelling of 31404689 in words is "thirty-one million, four hundred four thousand, six hundred eighty-nine".