12505531440 has 240 divisors, whose sum is σ = 40781318400. Its totient is φ = 3169082880.

The previous prime is 12505531429. The next prime is 12505531447. The reversal of 12505531440 is 4413550521.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 12505531398 and 12505531407.

It is not an unprimeable number, because it can be changed into a prime (12505531447) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13607301 + ... + 13608219.

It is an arithmetic number, because the mean of its divisors is an integer number (169922160).

Almost surely, 2^12505531440 is an apocalyptic number.

12505531440 is a gapful number since it is divisible by the number (10) 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 12505531440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20390659200).

12505531440 is an abundant number, since it is smaller than the sum of its proper divisors (28275786960).

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

12505531440 is a wasteful number, since it uses less digits than its factorization.

12505531440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1056 (or 1019 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

The spelling of 12505531440 in words is "twelve billion, five hundred five million, five hundred thirty-one thousand, four hundred forty".