31389290 has 8 divisors (see below), whose sum is σ = 56500740. Its totient is φ = 12555712.

The previous prime is 31389289. The next prime is 31389301. The reversal of 31389290 is 9298313.

It can be written as a sum of positive squares in 2 ways, for example, as 27050401 + 4338889 = 5201^2 + 2083^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 31389290.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1569455 + ... + 1569474.

Almost surely, 2^31389290 is an apocalyptic number.

31389290 is a deficient number, since it is larger than the sum of its proper divisors (25111450).

31389290 is a wasteful number, since it uses less digits than its factorization.

31389290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3138936.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 31389290 is about 5602.6145682172. The cubic root of 31389290 is about 315.4475539517.

The spelling of 31389290 in words is "thirty-one million, three hundred eighty-nine thousand, two hundred ninety".