31228385 has 4 divisors (see below), whose sum is σ = 37474068. Its totient is φ = 24982704.

The previous prime is 31228369. The next prime is 31228387. The reversal of 31228385 is 58382213.

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 24720784 + 6507601 = 4972^2 + 2551^2 .

It is a cyclic number.

It is not a de Polignac number, because 31228385 - 2⁴ = 31228369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31228387) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3122834 + ... + 3122843.

It is an arithmetic number, because the mean of its divisors is an integer number (9368517).

Almost surely, 2^31228385 is an apocalyptic number.

It is an amenable number.

31228385 is a deficient number, since it is larger than the sum of its proper divisors (6245683).

31228385 is an equidigital number, since it uses as much as digits as its factorization.

31228385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6245682.

The product of its digits is 11520, while the sum is 32.

The square root of 31228385 is about 5588.2363049535. The cubic root of 31228385 is about 314.9076238743.

It can be divided in two parts, 31228 and 385, that added together give a palindrome (31613).

The spelling of 31228385 in words is "thirty-one million, two hundred twenty-eight thousand, three hundred eighty-five".