31224143440 has 160 divisors (see below), whose sum is σ = 88521548544. Its totient is φ = 9998376960.

The previous prime is 31224143437. The next prime is 31224143443. The reversal of 31224143440 is 4434142213.

It is an interprime number because it is at equal distance from previous prime (31224143437) and next prime (31224143443).

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 31224143399 and 31224143408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31224143443) 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, 1234602 + ... + 1259638.

Almost surely, 2^31224143440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31224143440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44260774272).

31224143440 is an abundant number, since it is smaller than the sum of its proper divisors (57297405104).

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

31224143440 is a wasteful number, since it uses less digits than its factorization.

31224143440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25205 (or 25199 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 28.

Adding to 31224143440 its reverse (4434142213), we get a palindrome (35658285653).

The spelling of 31224143440 in words is "thirty-one billion, two hundred twenty-four million, one hundred forty-three thousand, four hundred forty".