31240321 has 8 divisors (see below), whose sum is σ = 36668480. Its totient is φ = 26053488.

The previous prime is 31240309. The next prime is 31240367. The reversal of 31240321 is 12304213.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 31240321 - 2⁹ = 31239809 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31240295 and 31240304.

It is not an unprimeable number, because it can be changed into a prime (31240301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 60051 + ... + 60568.

It is an arithmetic number, because the mean of its divisors is an integer number (4583560).

Almost surely, 2^31240321 is an apocalyptic number.

It is an amenable number.

31240321 is a deficient number, since it is larger than the sum of its proper divisors (5428159).

31240321 is a wasteful number, since it uses less digits than its factorization.

31240321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120663.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 31240321 is about 5589.3041606268. The cubic root of 31240321 is about 314.9477397135.

Adding to 31240321 its reverse (12304213), we get a palindrome (43544534).

The spelling of 31240321 in words is "thirty-one million, two hundred forty thousand, three hundred twenty-one".