31720743 has 12 divisors (see below), whose sum is σ = 46054008. Its totient is φ = 21038640.

The previous prime is 31720699. The next prime is 31720771. The reversal of 31720743 is 34702713.

It is not a de Polignac number, because 31720743 - 2¹² = 31716647 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31720543) 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 11 ways as a sum of consecutive naturals, for example, 7173 + ... + 10718.

It is an arithmetic number, because the mean of its divisors is an integer number (3837834).

Almost surely, 2^31720743 is an apocalyptic number.

31720743 is a deficient number, since it is larger than the sum of its proper divisors (14333265).

31720743 is a wasteful number, since it uses less digits than its factorization.

31720743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18094 (or 18091 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 27.

The square root of 31720743 is about 5632.1170975043. The cubic root of 31720743 is about 316.5539840383.

The spelling of 31720743 in words is "thirty-one million, seven hundred twenty thousand, seven hundred forty-three".