31489999 has 2 divisors, whose sum is σ = 31490000. Its totient is φ = 31489998.

The previous prime is 31489963. The next prime is 31490023. The reversal of 31489999 is 99998413.

It is a strong prime.

It is an emirp because it is prime and its reverse (99998413) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31489999 - 2¹⁷ = 31358927 is a prime.

31489999 is a modest number, since divided by 9999 gives 3148 as remainder.

It is a zygodrome in base 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31489919) by changing a digit.

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 as a sum of consecutive naturals, namely, 15744999 + 15745000.

It is an arithmetic number, because the mean of its divisors is an integer number (15745000).

Almost surely, 2^31489999 is an apocalyptic number.

31489999 is a deficient number, since it is larger than the sum of its proper divisors (1).

31489999 is an equidigital number, since it uses as much as digits as its factorization.

31489999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 629856, while the sum is 52.

The square root of 31489999 is about 5611.5950495381. The cubic root of 31489999 is about 315.7845531110.

The spelling of 31489999 in words is "thirty-one million, four hundred eighty-nine thousand, nine hundred ninety-nine".