21202212021 has 16 divisors (see below), whose sum is σ = 28444416000. Its totient is φ = 14047572528.

The previous prime is 21202212019. The next prime is 21202212029. The reversal of 21202212021 is 12021220212.

It is not a de Polignac number, because 21202212021 - 2¹ = 21202212019 is a prime.

It is a super-3 number, since 3×21202212021³ (a number of 32 digits) contains 333 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202212029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 509520 + ... + 549558.

It is an arithmetic number, because the mean of its divisors is an integer number (1777776000).

Almost surely, 2^21202212021 is an apocalyptic number.

It is an amenable number.

21202212021 is a deficient number, since it is larger than the sum of its proper divisors (7242203979).

21202212021 is a wasteful number, since it uses less digits than its factorization.

21202212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41128.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21202212021 its reverse (12021220212), we get a palindrome (33223432233).

The spelling of 21202212021 in words is "twenty-one billion, two hundred two million, two hundred twelve thousand, twenty-one".