31313340 has 72 divisors (see below), whose sum is σ = 97323408. Its totient is φ = 8144640.

The previous prime is 31313297. The next prime is 31313351. The reversal of 31313340 is 4331313.

31313340 is a `hidden beast` number, since 313 + 13 + 340 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

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 23 ways as a sum of consecutive naturals, for example, 5259 + ... + 9501.

It is an arithmetic number, because the mean of its divisors is an integer number (1351714).

Almost surely, 2^31313340 is an apocalyptic number.

31313340 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 31313340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48661704).

31313340 is an abundant number, since it is smaller than the sum of its proper divisors (66010068).

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

31313340 is a wasteful number, since it uses less digits than its factorization.

31313340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4299 (or 4294 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 18.

The square root of 31313340 is about 5595.8323777611. The cubic root of 31313340 is about 315.1929279207.

Adding to 31313340 its reverse (4331313), we get a palindrome (35644653).

The spelling of 31313340 in words is "thirty-one million, three hundred thirteen thousand, three hundred forty".