21211220122002 has 24 divisors (see below), whose sum is σ = 48661034398236. Its totient is φ = 6654500430336.

The previous prime is 21211220121983. The next prime is 21211220122031. The reversal of 21211220122002 is 20022102211212.

It is a happy number.

21211220122002 is a `hidden beast` number, since 21 + 211 + 220 + 12 + 200 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 20611972281681 + 599247840321 = 4540041^2 + 774111^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34658856103 + ... + 34658856714.

Almost surely, 2^{21211220122002} is an apocalyptic number.

21211220122002 is an abundant number, since it is smaller than the sum of its proper divisors (27449814276234).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21211220122002 is a wasteful number, since it uses less digits than its factorization.

21211220122002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69317712842 (or 69317712839 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21211220122002 its reverse (20022102211212), we get a palindrome (41233322333214).

The spelling of 21211220122002 in words is "twenty-one trillion, two hundred eleven billion, two hundred twenty million, one hundred twenty-two thousand, two".