31990745 has 4 divisors (see below), whose sum is σ = 38388900. Its totient is φ = 25592592.

The previous prime is 31990727. The next prime is 31990757. The reversal of 31990745 is 54709913.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3400336 + 28590409 = 1844^2 + 5347^2 .

It is a cyclic number.

It is not a de Polignac number, because 31990745 - 2⁸ = 31990489 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31990699 and 31990708.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3199070 + ... + 3199079.

It is an arithmetic number, because the mean of its divisors is an integer number (9597225).

Almost surely, 2^31990745 is an apocalyptic number.

It is an amenable number.

31990745 is a deficient number, since it is larger than the sum of its proper divisors (6398155).

31990745 is an equidigital number, since it uses as much as digits as its factorization.

31990745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6398154.

The product of its (nonzero) digits is 34020, while the sum is 38.

The square root of 31990745 is about 5656.0361561786. The cubic root of 31990745 is about 317.4496003659.

The spelling of 31990745 in words is "thirty-one million, nine hundred ninety thousand, seven hundred forty-five".