12638491420 has 24 divisors (see below), whose sum is σ = 26543500704. Its totient is φ = 5054888256.

The previous prime is 12638491417. The next prime is 12638491429. The reversal of 12638491420 is 2419483621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12638491429) 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, 221262 + ... + 272458.

It is an arithmetic number, because the mean of its divisors is an integer number (1105979196).

Almost surely, 2^12638491420 is an apocalyptic number.

12638491420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12638491420 is an abundant number, since it is smaller than the sum of its proper divisors (13905009284).

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

12638491420 is a wasteful number, since it uses less digits than its factorization.

12638491420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63549 (or 63547 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 40.

The spelling of 12638491420 in words is "twelve billion, six hundred thirty-eight million, four hundred ninety-one thousand, four hundred twenty".