12638545920 has 1152 divisors, whose sum is σ = 59241611520. Its totient is φ = 2406481920.

The previous prime is 12638545901. The next prime is 12638545921. The reversal of 12638545920 is 2954583621.

12638545920 is a `hidden beast` number, since 1 + 2 + 6 + 3 + 8 + 54 + 592 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (12638545921) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 92252092 + ... + 92252228.

It is an arithmetic number, because the mean of its divisors is an integer number (51425010).

Almost surely, 2^12638545920 is an apocalyptic number.

12638545920 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 12638545920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29620805760).

12638545920 is an abundant number, since it is smaller than the sum of its proper divisors (46603065600).

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

12638545920 is a wasteful number, since it uses less digits than its factorization.

12638545920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201 (or 178 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The spelling of 12638545920 in words is "twelve billion, six hundred thirty-eight million, five hundred forty-five thousand, nine hundred twenty".