21213246097 has 2 divisors, whose sum is σ = 21213246098. Its totient is φ = 21213246096.

The previous prime is 21213246079. The next prime is 21213246139. The reversal of 21213246097 is 79064231212.

Together with previous prime (21213246079) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20497362561 + 715883536 = 143169^2 + 26756^2 .

It is a cyclic number.

It is not a de Polignac number, because 21213246097 - 2¹¹ = 21213244049 is a prime.

It is not a weakly prime, because it can be changed into another prime (21213246007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606623048 + 10606623049.

It is an arithmetic number, because the mean of its divisors is an integer number (10606623049).

Almost surely, 2^21213246097 is an apocalyptic number.

It is an amenable number.

21213246097 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213246097 is an equidigital number, since it uses as much as digits as its factorization.

21213246097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 37.

The spelling of 21213246097 in words is "twenty-one billion, two hundred thirteen million, two hundred forty-six thousand, ninety-seven".