31240005 has 8 divisors (see below), whose sum is σ = 49984032. Its totient is φ = 16661328.

The previous prime is 31239977. The next prime is 31240019. The reversal of 31240005 is 50004213.

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

It is not a de Polignac number, because 31240005 - 2⁸ = 31239749 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15), and also a Moran number because the ratio is a prime number: 2082667 = 31240005 / (3 + 1 + 2 + 4 + 0 + 0 + 0 + 5).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1041319 + ... + 1041348.

It is an arithmetic number, because the mean of its divisors is an integer number (6248004).

Almost surely, 2^31240005 is an apocalyptic number.

It is an amenable number.

31240005 is a deficient number, since it is larger than the sum of its proper divisors (18744027).

31240005 is a wasteful number, since it uses less digits than its factorization.

31240005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2082675.

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 31240005 is about 5589.2758922780. The cubic root of 31240005 is about 314.9466777972.

Adding to 31240005 its reverse (50004213), we get a palindrome (81244218).

The spelling of 31240005 in words is "thirty-one million, two hundred forty thousand, five".