31231440240 has 640 divisors, whose sum is σ = 131895558144. Its totient is φ = 5902848000.

The previous prime is 31231440211. The next prime is 31231440259. The reversal of 31231440240 is 4204413213.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 31231440240.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 17056125 + ... + 17057955.

Almost surely, 2^31231440240 is an apocalyptic number.

31231440240 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 31231440240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65947779072).

31231440240 is an abundant number, since it is smaller than the sum of its proper divisors (100664117904).

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

31231440240 is a wasteful number, since it uses less digits than its factorization.

31231440240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1949 (or 1943 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 31231440240 its reverse (4204413213), we get a palindrome (35435853453).

The spelling of 31231440240 in words is "thirty-one billion, two hundred thirty-one million, four hundred forty thousand, two hundred forty".