21996838247 has 2 divisors, whose sum is σ = 21996838248. Its totient is φ = 21996838246.

The previous prime is 21996838207. The next prime is 21996838267. The reversal of 21996838247 is 74283869912.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21996838247 - 2¹² = 21996834151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21996838207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10998419123 + 10998419124.

It is an arithmetic number, because the mean of its divisors is an integer number (10998419124).

Almost surely, 2^21996838247 is an apocalyptic number.

21996838247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21996838247 is an equidigital number, since it uses as much as digits as its factorization.

21996838247 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10450944, while the sum is 59.

The spelling of 21996838247 in words is "twenty-one billion, nine hundred ninety-six million, eight hundred thirty-eight thousand, two hundred forty-seven".