21219999738967 has 2 divisors, whose sum is σ = 21219999738968. Its totient is φ = 21219999738966.

The previous prime is 21219999738947. The next prime is 21219999739027. The reversal of 21219999738967 is 76983799991212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21219999738967 - 2²³ = 21219991350359 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21219999738947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10609999869483 + 10609999869484.

It is an arithmetic number, because the mean of its divisors is an integer number (10609999869484).

Almost surely, 2^{21219999738967} is an apocalyptic number.

21219999738967 is a deficient number, since it is larger than the sum of its proper divisors (1).

21219999738967 is an equidigital number, since it uses as much as digits as its factorization.

21219999738967 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1666598976, while the sum is 82.

The spelling of 21219999738967 in words is "twenty-one trillion, two hundred nineteen billion, nine hundred ninety-nine million, seven hundred thirty-eight thousand, nine hundred sixty-seven".