21996838207 has 2 divisors, whose sum is σ = 21996838208. Its totient is φ = 21996838206.

The previous prime is 21996838163. The next prime is 21996838247. The reversal of 21996838207 is 70283869912.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21996838207 is a prime.

It is a super-2 number, since 2×21996838207² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21996838247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10998419103 + 10998419104.

It is an arithmetic number, because the mean of its divisors is an integer number (10998419104).

Almost surely, 2^21996838207 is an apocalyptic number.

21996838207 is a deficient number, since it is larger than the sum of its proper divisors (1).

21996838207 is an equidigital number, since it uses as much as digits as its factorization.

21996838207 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2612736, while the sum is 55.

The spelling of 21996838207 in words is "twenty-one billion, nine hundred ninety-six million, eight hundred thirty-eight thousand, two hundred seven".