31379947 has 2 divisors, whose sum is σ = 31379948. Its totient is φ = 31379946.

The previous prime is 31379939. The next prime is 31379969. The reversal of 31379947 is 74997313.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31379947 - 2³ = 31379939 is a prime.

It is a super-3 number, since 3×31379947³ (a number of 23 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (31371947) 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 as a sum of consecutive naturals, namely, 15689973 + 15689974.

It is an arithmetic number, because the mean of its divisors is an integer number (15689974).

Almost surely, 2^31379947 is an apocalyptic number.

31379947 is a deficient number, since it is larger than the sum of its proper divisors (1).

31379947 is an equidigital number, since it uses as much as digits as its factorization.

31379947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 142884, while the sum is 43.

The square root of 31379947 is about 5601.7806990278. The cubic root of 31379947 is about 315.4162532654.

The spelling of 31379947 in words is "thirty-one million, three hundred seventy-nine thousand, nine hundred forty-seven".