31397439 has 8 divisors (see below), whose sum is σ = 42836992. Its totient is φ = 20444760.

The previous prime is 31397437. The next prime is 31397441. The reversal of 31397439 is 93479313.

It is an interprime number because it is at equal distance from previous prime (31397437) and next prime (31397441).

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

It is not a de Polignac number, because 31397439 - 2¹ = 31397437 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31397397 and 31397406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31397437) 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 7 ways as a sum of consecutive naturals, for example, 121567 + ... + 121824.

It is an arithmetic number, because the mean of its divisors is an integer number (5354624).

Almost surely, 2^31397439 is an apocalyptic number.

31397439 is a deficient number, since it is larger than the sum of its proper divisors (11439553).

31397439 is a wasteful number, since it uses less digits than its factorization.

31397439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243437.

The product of its digits is 61236, while the sum is 39.

The square root of 31397439 is about 5603.3417707650. The cubic root of 31397439 is about 315.4748494581.

The spelling of 31397439 in words is "thirty-one million, three hundred ninety-seven thousand, four hundred thirty-nine".