21211220122 has 8 divisors (see below), whose sum is σ = 31911243156. Its totient is φ = 10574139072.

The previous prime is 21211220113. The next prime is 21211220143. The reversal of 21211220122 is 22102211212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21164721361 + 46498761 = 145481^2 + 6819^2 .

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

It is a super-3 number, since 3×21211220122³ (a number of 32 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21211220096 and 21211220105.

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, 15734653 + ... + 15736000.

Almost surely, 2^21211220122 is an apocalyptic number.

21211220122 is a deficient number, since it is larger than the sum of its proper divisors (10700023034).

21211220122 is a wasteful number, since it uses less digits than its factorization.

21211220122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31470992.

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

Adding to 21211220122 its reverse (22102211212), we get a palindrome (43313431334).

The spelling of 21211220122 in words is "twenty-one billion, two hundred eleven million, two hundred twenty thousand, one hundred twenty-two".