12621997 has 2 divisors, whose sum is σ = 12621998. Its totient is φ = 12621996.

The previous prime is 12621979. The next prime is 12622013. The reversal of 12621997 is 79912621.

12621997 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

Together with previous prime (12621979) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10850436 + 1771561 = 3294^2 + 1331^2 .

It is an emirp because it is prime and its reverse (79912621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12621997 - 2²³ = 4233389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12621967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6310998 + 6310999.

It is an arithmetic number, because the mean of its divisors is an integer number (6310999).

Almost surely, 2^12621997 is an apocalyptic number.

It is an amenable number.

12621997 is a deficient number, since it is larger than the sum of its proper divisors (1).

12621997 is an equidigital number, since it uses as much as digits as its factorization.

12621997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 37.

The square root of 12621997 is about 3552.7449950707. The cubic root of 12621997 is about 232.8320118806.

The spelling of 12621997 in words is "twelve million, six hundred twenty-one thousand, nine hundred ninety-seven".