21402222216637 has 2 divisors, whose sum is σ = 21402222216638. Its totient is φ = 21402222216636.

The previous prime is 21402222216601. The next prime is 21402222216677. The reversal of 21402222216637 is 73661222220412.

It is an a-pointer prime, because the next prime (21402222216677) can be obtained adding 21402222216637 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15195292756996 + 6206929459641 = 3898114^2 + 2491371^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21402222216637 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21402222216637.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21402222216677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10701111108318 + 10701111108319.

It is an arithmetic number, because the mean of its divisors is an integer number (10701111108319).

Almost surely, 2^{21402222216637} is an apocalyptic number.

It is an amenable number.

21402222216637 is a deficient number, since it is larger than the sum of its proper divisors (1).

21402222216637 is an equidigital number, since it uses as much as digits as its factorization.

21402222216637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 193536, while the sum is 40.

The spelling of 21402222216637 in words is "twenty-one trillion, four hundred two billion, two hundred twenty-two million, two hundred sixteen thousand, six hundred thirty-seven".