21223201671 has 24 divisors (see below), whose sum is σ = 35145680544. Its totient is φ = 12089275200.

The previous prime is 21223201589. The next prime is 21223201687. The reversal of 21223201671 is 17610232212.

It is not a de Polignac number, because 21223201671 - 2⁷ = 21223201543 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21223201691) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 511380 + ... + 551321.

It is an arithmetic number, because the mean of its divisors is an integer number (1464403356).

Almost surely, 2^21223201671 is an apocalyptic number.

21223201671 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21223201671 is a deficient number, since it is larger than the sum of its proper divisors (13922478873).

21223201671 is a wasteful number, since it uses less digits than its factorization.

21223201671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1063031 (or 1063028 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

Adding to 21223201671 its reverse (17610232212), we get a palindrome (38833433883).

The spelling of 21223201671 in words is "twenty-one billion, two hundred twenty-three million, two hundred one thousand, six hundred seventy-one".