21223201642 has 8 divisors (see below), whose sum is σ = 33707437956. Its totient is φ = 9987388992.

The previous prime is 21223201589. The next prime is 21223201687. The reversal of 21223201642 is 24610232212.

It can be written as a sum of positive squares in 2 ways, for example, as 20417266321 + 805935321 = 142889^2 + 28389^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 312105873 + ... + 312105940.

Almost surely, 2^21223201642 is an apocalyptic number.

21223201642 is a deficient number, since it is larger than the sum of its proper divisors (12484236314).

21223201642 is a wasteful number, since it uses less digits than its factorization.

21223201642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624211832.

The product of its (nonzero) digits is 2304, while the sum is 25.

Adding to 21223201642 its reverse (24610232212), we get a palindrome (45833433854).

The spelling of 21223201642 in words is "twenty-one billion, two hundred twenty-three million, two hundred one thousand, six hundred forty-two".