31382640 has 200 divisors, whose sum is σ = 113430240. Its totient is φ = 8031744.

The previous prime is 31382591. The next prime is 31382653. The reversal of 31382640 is 4628313.

It is a happy number.

31382640 is a `hidden beast` number, since 3 + 13 + 8 + 2 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 187837 + ... + 188003.

Almost surely, 2^31382640 is an apocalyptic number.

31382640 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 31382640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56715120).

31382640 is an abundant number, since it is smaller than the sum of its proper divisors (82047600).

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

31382640 is a wasteful number, since it uses less digits than its factorization.

31382640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221 (or 206 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 31382640 is about 5602.0210638661. The cubic root of 31382640 is about 315.4252759243.

It can be divided in two parts, 3138 and 2640, that added together give a triangular number (5778 = T₁₀₇).

The spelling of 31382640 in words is "thirty-one million, three hundred eighty-two thousand, six hundred forty".