31660140 has 96 divisors (see below), whose sum is σ = 92252160. Its totient is φ = 8107776.

The previous prime is 31660129. The next prime is 31660147. The reversal of 31660140 is 4106613.

It is not an unprimeable number, because it can be changed into a prime (31660147) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 290406 + ... + 290514.

It is an arithmetic number, because the mean of its divisors is an integer number (960960).

Almost surely, 2^31660140 is an apocalyptic number.

31660140 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 31660140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46126080).

31660140 is an abundant number, since it is smaller than the sum of its proper divisors (60592020).

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

31660140 is a wasteful number, since it uses less digits than its factorization.

31660140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271 (or 269 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 31660140 is about 5626.7343992764. The cubic root of 31660140 is about 316.3522616588.

Adding to 31660140 its reverse (4106613), we get a palindrome (35766753).

The spelling of 31660140 in words is "thirty-one million, six hundred sixty thousand, one hundred forty".