31290047 has 4 divisors (see below), whose sum is σ = 33130656. Its totient is φ = 29449440.

The previous prime is 31290029. The next prime is 31290059. The reversal of 31290047 is 74009213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74009213 = 37 ⋅2000249.

It is not a de Polignac number, because 31290047 - 2¹⁸ = 31027903 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31289998 and 31290025.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31290247) 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, 920279 + ... + 920312.

It is an arithmetic number, because the mean of its divisors is an integer number (8282664).

Almost surely, 2^31290047 is an apocalyptic number.

31290047 is a deficient number, since it is larger than the sum of its proper divisors (1840609).

31290047 is a wasteful number, since it uses less digits than its factorization.

31290047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1840608.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 31290047 is about 5593.7507094972. The cubic root of 31290047 is about 315.1147545281.

The spelling of 31290047 in words is "thirty-one million, two hundred ninety thousand, forty-seven".