31040340 has 96 divisors (see below), whose sum is σ = 92123136. Its totient is φ = 7793280.

The previous prime is 31040329. The next prime is 31040369. The reversal of 31040340 is 4304013.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 114405 + ... + 114675.

It is an arithmetic number, because the mean of its divisors is an integer number (959616).

Almost surely, 2^31040340 is an apocalyptic number.

31040340 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 31040340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46061568).

31040340 is an abundant number, since it is smaller than the sum of its proper divisors (61082796).

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

31040340 is a wasteful number, since it uses less digits than its factorization.

31040340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 389 (or 387 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 31040340 is about 5571.3858240118. The cubic root of 31040340 is about 314.2742677846.

Adding to 31040340 its reverse (4304013), we get a palindrome (35344353).

The spelling of 31040340 in words is "thirty-one million, forty thousand, three hundred forty".