21202120222002 has 20 divisors (see below), whose sum is σ = 47508454571886. Its totient is φ = 7067373407280.

The previous prime is 21202120221979. The next prime is 21202120222037. The reversal of 21202120222002 is 20022202120212.

It can be written as a sum of positive squares in only one way, i.e., 17608589595081 + 3593530626921 = 4196259^2 + 1895661^2 .

It is a super-2 number, since 2×21202120222002² (a number of 27 digits) contains 22 as substring.

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 9 ways as a sum of consecutive naturals, for example, 65438642499 + ... + 65438642822.

Almost surely, 2^{21202120222002} is an apocalyptic number.

21202120222002 is an abundant number, since it is smaller than the sum of its proper divisors (26306334349884).

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

21202120222002 is a wasteful number, since it uses less digits than its factorization.

21202120222002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130877285335 (or 130877285326 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21202120222002 its reverse (20022202120212), we get a palindrome (41224322342214).

The spelling of 21202120222002 in words is "twenty-one trillion, two hundred two billion, one hundred twenty million, two hundred twenty-two thousand, two".