31684380 has 144 divisors (see below), whose sum is σ = 111273120. Its totient is φ = 6676992.

The previous prime is 31684351. The next prime is 31684463. The reversal of 31684380 is 8348613.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 37806 + ... + 38634.

It is an arithmetic number, because the mean of its divisors is an integer number (772730).

Almost surely, 2^31684380 is an apocalyptic number.

31684380 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31684380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55636560).

31684380 is an abundant number, since it is smaller than the sum of its proper divisors (79588740).

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

31684380 is a wasteful number, since it uses less digits than its factorization.

31684380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 868 (or 859 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 31684380 is about 5628.8879896477. The cubic root of 31684380 is about 316.4329774801.

The spelling of 31684380 in words is "thirty-one million, six hundred eighty-four thousand, three hundred eighty".