12638545901 has 2 divisors, whose sum is σ = 12638545902. Its totient is φ = 12638545900.

The previous prime is 12638545889. The next prime is 12638545921. The reversal of 12638545901 is 10954583621.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12000983401 + 637562500 = 109549^2 + 25250^2 .

It is a cyclic number.

It is not a de Polignac number, because 12638545901 - 2¹⁴ = 12638529517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12638545921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6319272950 + 6319272951.

It is an arithmetic number, because the mean of its divisors is an integer number (6319272951).

Almost surely, 2^12638545901 is an apocalyptic number.

It is an amenable number.

12638545901 is a deficient number, since it is larger than the sum of its proper divisors (1).

12638545901 is an equidigital number, since it uses as much as digits as its factorization.

12638545901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 259200, while the sum is 44.

The spelling of 12638545901 in words is "twelve billion, six hundred thirty-eight million, five hundred forty-five thousand, nine hundred one".