31708947 has 4 divisors (see below), whose sum is σ = 42278600. Its totient is φ = 21139296.

The previous prime is 31708933. The next prime is 31708969. The reversal of 31708947 is 74980713.

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

It is not a de Polignac number, because 31708947 - 2¹⁵ = 31676179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31708907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5284822 + ... + 5284827.

It is an arithmetic number, because the mean of its divisors is an integer number (10569650).

Almost surely, 2^31708947 is an apocalyptic number.

31708947 is a deficient number, since it is larger than the sum of its proper divisors (10569653).

31708947 is a wasteful number, since it uses less digits than its factorization.

31708947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10569652.

The product of its (nonzero) digits is 42336, while the sum is 39.

The square root of 31708947 is about 5631.0697917891. The cubic root of 31708947 is about 316.5147401724.

The spelling of 31708947 in words is "thirty-one million, seven hundred eight thousand, nine hundred forty-seven".