20210221221012 has 18 divisors (see below), whose sum is σ = 51086948086538. Its totient is φ = 6736740406992.

The previous prime is 20210221220911. The next prime is 20210221221019. The reversal of 20210221221012 is 21012212201202.

It is a happy number.

20210221221012 is a `hidden beast` number, since 2 + 0 + 210 + 221 + 221 + 0 + 12 = 666.

It can be written as a sum of positive squares in only one way, i.e., 20033448063876 + 176773157136 = 4475874^2 + 420444^2 .

It is a tau number, because it is divible by the number of its divisors (18).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20210221221019) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 280697516923 + ... + 280697516994.

Almost surely, 2^{20210221221012} is an apocalyptic number.

It is an amenable number.

20210221221012 is an abundant number, since it is smaller than the sum of its proper divisors (30876726865526).

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

20210221221012 is a wasteful number, since it uses less digits than its factorization.

20210221221012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 561395033927 (or 561395033922 counting only the distinct ones).

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

Adding to 20210221221012 its reverse (21012212201202), we get a palindrome (41222433422214).

The spelling of 20210221221012 in words is "twenty trillion, two hundred ten billion, two hundred twenty-one million, two hundred twenty-one thousand, twelve".