31151389 has 2 divisors, whose sum is σ = 31151390. Its totient is φ = 31151388.

The previous prime is 31151383. The next prime is 31151443. The reversal of 31151389 is 98315113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30415225 + 736164 = 5515^2 + 858^2 .

It is a cyclic number.

It is not a de Polignac number, because 31151389 - 2³ = 31151381 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31151389.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31151381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15575694 + 15575695.

It is an arithmetic number, because the mean of its divisors is an integer number (15575695).

Almost surely, 2^31151389 is an apocalyptic number.

It is an amenable number.

31151389 is a deficient number, since it is larger than the sum of its proper divisors (1).

31151389 is an equidigital number, since it uses as much as digits as its factorization.

31151389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3240, while the sum is 31.

The square root of 31151389 is about 5581.3429387559. The cubic root of 31151389 is about 314.6486011715.

The spelling of 31151389 in words is "thirty-one million, one hundred fifty-one thousand, three hundred eighty-nine".