31440243 has 8 divisors (see below), whose sum is σ = 42152656. Its totient is φ = 20844000.

The previous prime is 31440223. The next prime is 31440251. The reversal of 31440243 is 34204413.

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

It is not a de Polignac number, because 31440243 - 2¹⁷ = 31309171 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31440223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28408 + ... + 29493.

It is an arithmetic number, because the mean of its divisors is an integer number (5269082).

Almost surely, 2^31440243 is an apocalyptic number.

31440243 is a deficient number, since it is larger than the sum of its proper divisors (10712413).

31440243 is a wasteful number, since it uses less digits than its factorization.

31440243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58085.

The product of its (nonzero) digits is 1152, while the sum is 21.

The square root of 31440243 is about 5607.1599763160. The cubic root of 31440243 is about 315.6181462159.

Adding to 31440243 its reverse (34204413), we get a palindrome (65644656).

The spelling of 31440243 in words is "thirty-one million, four hundred forty thousand, two hundred forty-three".