21001221022 has 8 divisors (see below), whose sum is σ = 31512132072. Its totient is φ = 10497177000.

The previous prime is 21001221013. The next prime is 21001221029. The reversal of 21001221022 is 22012210012.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 21001220993 and 21001221011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001221029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1709104 + ... + 1721347.

It is an arithmetic number, because the mean of its divisors is an integer number (3939016509).

Almost surely, 2^21001221022 is an apocalyptic number.

21001221022 is a deficient number, since it is larger than the sum of its proper divisors (10510911050).

21001221022 is a wasteful number, since it uses less digits than its factorization.

21001221022 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3433514.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21001221022 its reverse (22012210012), we get a palindrome (43013431034).

The spelling of 21001221022 in words is "twenty-one billion, one million, two hundred twenty-one thousand, twenty-two".