21212020102122 has 48 divisors (see below), whose sum is σ = 48428321472960. Its totient is φ = 6691605431616.

The previous prime is 21212020102099. The next prime is 21212020102123. The reversal of 21212020102122 is 22120102021212.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 21212020102095 and 21212020102104.

It is not an unprimeable number, because it can be changed into a prime (21212020102123) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31739323 + ... + 32400750.

It is an arithmetic number, because the mean of its divisors is an integer number (1008923364020).

Almost surely, 2^{21212020102122} is an apocalyptic number.

21212020102122 is an abundant number, since it is smaller than the sum of its proper divisors (27216301370838).

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

21212020102122 is a wasteful number, since it uses less digits than its factorization.

21212020102122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64141067 (or 64141064 counting only the distinct ones).

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

Adding to 21212020102122 its reverse (22120102021212), we get a palindrome (43332122123334).

The spelling of 21212020102122 in words is "twenty-one trillion, two hundred twelve billion, twenty million, one hundred two thousand, one hundred twenty-two".