31232423440 has 40 divisors (see below), whose sum is σ = 76437250560. Its totient is φ = 11835444096.

The previous prime is 31232423389. The next prime is 31232423449. The reversal of 31232423440 is 4432423213.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×31232423440² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31232423399 and 31232423408.

It is not an unprimeable number, because it can be changed into a prime (31232423449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10272304 + ... + 10275343.

It is an arithmetic number, because the mean of its divisors is an integer number (1910931264).

Almost surely, 2^31232423440 is an apocalyptic number.

It is an amenable number.

31232423440 is an abundant number, since it is smaller than the sum of its proper divisors (45204827120).

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

31232423440 is a wasteful number, since it uses less digits than its factorization.

31232423440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20547679 (or 20547673 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 28.

Adding to 31232423440 its reverse (4432423213), we get a palindrome (35664846653).

The spelling of 31232423440 in words is "thirty-one billion, two hundred thirty-two million, four hundred twenty-three thousand, four hundred forty".