21201220122 has 8 divisors (see below), whose sum is σ = 42402440256. Its totient is φ = 7067073372.

The previous prime is 21201220049. The next prime is 21201220123. The reversal of 21201220122 is 22102210212.

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

21201220122 is an admirable number.

It is a super-2 number, since 2×21201220122² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21201220123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1766768338 + ... + 1766768349.

It is an arithmetic number, because the mean of its divisors is an integer number (5300305032).

Almost surely, 2^21201220122 is an apocalyptic number.

21201220122 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21201220122 is a wasteful number, since it uses less digits than its factorization.

21201220122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3533536692.

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

Adding to 21201220122 its reverse (22102210212), we get a palindrome (43303430334).

The spelling of 21201220122 in words is "twenty-one billion, two hundred one million, two hundred twenty thousand, one hundred twenty-two".