31243240140 has 384 divisors, whose sum is σ = 109084631040. Its totient is φ = 6522550272.

The previous prime is 31243240129. The next prime is 31243240151. The reversal of 31243240140 is 4104234213.

It is an interprime number because it is at equal distance from previous prime (31243240129) and next prime (31243240151).

It is a super-3 number, since 3×31243240140³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 31243240140.

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, 28480072 + ... + 28481168.

It is an arithmetic number, because the mean of its divisors is an integer number (284074560).

Almost surely, 2^31243240140 is an apocalyptic number.

31243240140 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 31243240140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54542315520).

31243240140 is an abundant number, since it is smaller than the sum of its proper divisors (77841390900).

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

31243240140 is a wasteful number, since it uses less digits than its factorization.

31243240140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1261 (or 1259 counting only the distinct ones).

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

Adding to 31243240140 its reverse (4104234213), we get a palindrome (35347474353).

The spelling of 31243240140 in words is "thirty-one billion, two hundred forty-three million, two hundred forty thousand, one hundred forty".