31109940 has 96 divisors (see below), whose sum is σ = 98703360. Its totient is φ = 8131968.

The previous prime is 31109921. The next prime is 31109951. The reversal of 31109940 is 4990113.

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 31 ways as a sum of consecutive naturals, for example, 28077 + ... + 29163.

It is an arithmetic number, because the mean of its divisors is an integer number (1028160).

Almost surely, 2^31109940 is an apocalyptic number.

31109940 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 31109940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49351680).

31109940 is an abundant number, since it is smaller than the sum of its proper divisors (67593420).

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

31109940 is a wasteful number, since it uses less digits than its factorization.

31109940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1158 (or 1150 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 31109940 is about 5577.6285283264. The cubic root of 31109940 is about 314.5089855831.

The spelling of 31109940 in words is "thirty-one million, one hundred nine thousand, nine hundred forty".