21220032021 has 16 divisors (see below), whose sum is σ = 28908125184. Its totient is φ = 13839579504.

The previous prime is 21220032017. The next prime is 21220032059. The reversal of 21220032021 is 12023002212.

It is a happy number.

It is not a de Polignac number, because 21220032021 - 2² = 21220032017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220032091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 298866 + ... + 362988.

It is an arithmetic number, because the mean of its divisors is an integer number (1806757824).

Almost surely, 2^21220032021 is an apocalyptic number.

It is an amenable number.

21220032021 is a deficient number, since it is larger than the sum of its proper divisors (7688093163).

21220032021 is a wasteful number, since it uses less digits than its factorization.

21220032021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66520.

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 21220032021 its reverse (12023002212), we get a palindrome (33243034233).

The spelling of 21220032021 in words is "twenty-one billion, two hundred twenty million, thirty-two thousand, twenty-one".