31340431 has 4 divisors (see below), whose sum is σ = 31380552. Its totient is φ = 31300312.

The previous prime is 31340423. The next prime is 31340447. The reversal of 31340431 is 13404313.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31340431 - 2³ = 31340423 is a prime.

It is a super-2 number, since 2×31340431² = 1964445230531522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31340399 and 31340408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31340471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18865 + ... + 20458.

It is an arithmetic number, because the mean of its divisors is an integer number (7845138).

Almost surely, 2^31340431 is an apocalyptic number.

31340431 is a deficient number, since it is larger than the sum of its proper divisors (40121).

31340431 is an equidigital number, since it uses as much as digits as its factorization.

31340431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40120.

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 31340431 is about 5598.2524951988. The cubic root of 31340431 is about 315.2837989924.

Adding to 31340431 its reverse (13404313), we get a palindrome (44744744).

The spelling of 31340431 in words is "thirty-one million, three hundred forty thousand, four hundred thirty-one".