31438140 has 24 divisors (see below), whose sum is σ = 88026960. Its totient is φ = 8383488.

The previous prime is 31438133. The next prime is 31438153. The reversal of 31438140 is 4183413.

It is a self number, because there is not a number n which added to its sum of digits gives 31438140.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 261925 + ... + 262044.

It is an arithmetic number, because the mean of its divisors is an integer number (3667790).

Almost surely, 2^31438140 is an apocalyptic number.

31438140 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31438140 is an abundant number, since it is smaller than the sum of its proper divisors (56588820).

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

31438140 is a wasteful number, since it uses less digits than its factorization.

31438140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523981 (or 523979 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 31438140 is about 5606.9724450901. The cubic root of 31438140 is about 315.6111089531.

The spelling of 31438140 in words is "thirty-one million, four hundred thirty-eight thousand, one hundred forty".