21022221907 has 2 divisors, whose sum is σ = 21022221908. Its totient is φ = 21022221906.

The previous prime is 21022221893. The next prime is 21022221923. The reversal of 21022221907 is 70912222012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21022221907 - 2²³ = 21013833299 is a prime.

It is not a weakly prime, because it can be changed into another prime (21022221107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511110953 + 10511110954.

It is an arithmetic number, because the mean of its divisors is an integer number (10511110954).

Almost surely, 2^21022221907 is an apocalyptic number.

21022221907 is a deficient number, since it is larger than the sum of its proper divisors (1).

21022221907 is an equidigital number, since it uses as much as digits as its factorization.

21022221907 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 28.

Adding to 21022221907 its reverse (70912222012), we get a palindrome (91934443919).

The spelling of 21022221907 in words is "twenty-one billion, twenty-two million, two hundred twenty-one thousand, nine hundred seven".