21214036421197 has 4 divisors (see below), whose sum is σ = 21246130274236. Its totient is φ = 21181942568160.

The previous prime is 21214036421189. The next prime is 21214036421203. The reversal of 21214036421197 is 79112463041212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14814446894116 + 6399589527081 = 3848954^2 + 2529741^2 .

It is a cyclic number.

It is not a de Polignac number, because 21214036421197 - 2³ = 21214036421189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21214036421117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16046925528 + ... + 16046926849.

It is an arithmetic number, because the mean of its divisors is an integer number (5311532568559).

Almost surely, 2^{21214036421197} is an apocalyptic number.

It is an amenable number.

21214036421197 is a deficient number, since it is larger than the sum of its proper divisors (32093853039).

21214036421197 is an equidigital number, since it uses as much as digits as its factorization.

21214036421197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32093853038.

The product of its (nonzero) digits is 145152, while the sum is 43.

The spelling of 21214036421197 in words is "twenty-one trillion, two hundred fourteen billion, thirty-six million, four hundred twenty-one thousand, one hundred ninety-seven".