31873240 has 64 divisors (see below), whose sum is σ = 83232000. Its totient is φ = 10758528.

The previous prime is 31873229. The next prime is 31873271. The reversal of 31873240 is 4237813.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 31873199 and 31873208.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17911 + ... + 19609.

It is an arithmetic number, because the mean of its divisors is an integer number (1300500).

Almost surely, 2^31873240 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31873240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41616000).

31873240 is an abundant number, since it is smaller than the sum of its proper divisors (51358760).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31873240 is a wasteful number, since it uses less digits than its factorization.

31873240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1784 (or 1780 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 31873240 is about 5645.6390249466. The cubic root of 31873240 is about 317.0604494843.

The spelling of 31873240 in words is "thirty-one million, eight hundred seventy-three thousand, two hundred forty".