31431745 has 8 divisors (see below), whose sum is σ = 37748520. Its totient is φ = 25125120.

The previous prime is 31431739. The next prime is 31431749. The reversal of 31431745 is 54713413.

It can be written as a sum of positive squares in 4 ways, for example, as 9790641 + 21641104 = 3129^2 + 4652^2 .

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

It is not a de Polignac number, because 31431745 - 2⁵ = 31431713 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31431749) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9351 + ... + 12259.

It is an arithmetic number, because the mean of its divisors is an integer number (4718565).

Almost surely, 2^31431745 is an apocalyptic number.

It is an amenable number.

31431745 is a deficient number, since it is larger than the sum of its proper divisors (6316775).

31431745 is a wasteful number, since it uses less digits than its factorization.

31431745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5075.

The product of its digits is 5040, while the sum is 28.

The square root of 31431745 is about 5606.4021439779. The cubic root of 31431745 is about 315.5897074546.

The spelling of 31431745 in words is "thirty-one million, four hundred thirty-one thousand, seven hundred forty-five".