21210021002122 has 4 divisors (see below), whose sum is σ = 31815031503186. Its totient is φ = 10605010501060.

The previous prime is 21210021002101. The next prime is 21210021002171. The reversal of 21210021002122 is 22120012001212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 19120409090721 + 2089611911401 = 4372689^2 + 1445549^2 .

It is a super-3 number, since 3×21210021002122³ (a number of 41 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21210021002096 and 21210021002105.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5302505250529 + ... + 5302505250532.

Almost surely, 2^{21210021002122} is an apocalyptic number.

21210021002122 is a deficient number, since it is larger than the sum of its proper divisors (10605010501064).

21210021002122 is a wasteful number, since it uses less digits than its factorization.

21210021002122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10605010501063.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21210021002122 its reverse (22120012001212), we get a palindrome (43330033003334).

The spelling of 21210021002122 in words is "twenty-one trillion, two hundred ten billion, twenty-one million, two thousand, one hundred twenty-two".