31994140 has 12 divisors (see below), whose sum is σ = 67187736. Its totient is φ = 12797648.

The previous prime is 31994117. The next prime is 31994147. The reversal of 31994140 is 4149913.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31994147) 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 3 ways as a sum of consecutive naturals, for example, 799834 + ... + 799873.

It is an arithmetic number, because the mean of its divisors is an integer number (5598978).

Almost surely, 2^31994140 is an apocalyptic number.

It is an amenable number.

31994140 is an abundant number, since it is smaller than the sum of its proper divisors (35193596).

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

31994140 is a wasteful number, since it uses less digits than its factorization.

31994140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1599716 (or 1599714 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 31994140 is about 5656.3362700603. The cubic root of 31994140 is about 317.4608296894.

The spelling of 31994140 in words is "thirty-one million, nine hundred ninety-four thousand, one hundred forty".