20031312440 has 16 divisors (see below), whose sum is σ = 45070453080. Its totient is φ = 8012524960.

The previous prime is 20031312437. The next prime is 20031312461. The reversal of 20031312440 is 4421313002.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250391366 + ... + 250391445.

Almost surely, 2^20031312440 is an apocalyptic number.

20031312440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20031312440 is an abundant number, since it is smaller than the sum of its proper divisors (25039140640).

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

20031312440 is a wasteful number, since it uses less digits than its factorization.

20031312440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500782822 (or 500782818 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 20031312440 its reverse (4421313002), we get a palindrome (24452625442).

The spelling of 20031312440 in words is "twenty billion, thirty-one million, three hundred twelve thousand, four hundred forty".