31442743 has 4 divisors (see below), whose sum is σ = 31516128. Its totient is φ = 31369360.

The previous prime is 31442737. The next prime is 31442783. The reversal of 31442743 is 34724413.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34724413 = 151 ⋅229963.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31442743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31442783) 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, 36046 + ... + 36907.

It is an arithmetic number, because the mean of its divisors is an integer number (7879032).

Almost surely, 2^31442743 is an apocalyptic number.

31442743 is a deficient number, since it is larger than the sum of its proper divisors (73385).

31442743 is an equidigital number, since it uses as much as digits as its factorization.

31442743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73384.

The product of its digits is 8064, while the sum is 28.

The square root of 31442743 is about 5607.3829011402. The cubic root of 31442743 is about 315.6265115505.

The spelling of 31442743 in words is "thirty-one million, four hundred forty-two thousand, seven hundred forty-three".