12540989808 has 80 divisors (see below), whose sum is σ = 36044002560. Its totient is φ = 4174905024.

The previous prime is 12540989731. The next prime is 12540989831. The reversal of 12540989808 is 80898904521.

12540989808 is a `hidden beast` number, since 1 + 2 + 540 + 9 + 8 + 98 + 0 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 321541 + ... + 358427.

It is an arithmetic number, because the mean of its divisors is an integer number (450550032).

Almost surely, 2^12540989808 is an apocalyptic number.

12540989808 is a gapful number since it is divisible by the number (18) 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 12540989808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18022001280).

12540989808 is an abundant number, since it is smaller than the sum of its proper divisors (23503012752).

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

12540989808 is a wasteful number, since it uses less digits than its factorization.

12540989808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37691 (or 37679 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 54.

The spelling of 12540989808 in words is "twelve billion, five hundred forty million, nine hundred eighty-nine thousand, eight hundred eight".