12721238357 has 2 divisors, whose sum is σ = 12721238358. Its totient is φ = 12721238356.

The previous prime is 12721238353. The next prime is 12721238377. The reversal of 12721238357 is 75383212721.

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., 7480347121 + 5240891236 = 86489^2 + 72394^2 .

It is a cyclic number.

It is not a de Polignac number, because 12721238357 - 2² = 12721238353 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12721238353) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6360619178 + 6360619179.

It is an arithmetic number, because the mean of its divisors is an integer number (6360619179).

Almost surely, 2^12721238357 is an apocalyptic number.

It is an amenable number.

12721238357 is a deficient number, since it is larger than the sum of its proper divisors (1).

12721238357 is an equidigital number, since it uses as much as digits as its factorization.

12721238357 is an evil number, because the sum of its binary digits is even.

The product of its digits is 141120, while the sum is 41.

The spelling of 12721238357 in words is "twelve billion, seven hundred twenty-one million, two hundred thirty-eight thousand, three hundred fifty-seven".