202121000021 has 8 divisors (see below), whose sum is σ = 203194034688. Its totient is φ = 201048120000.

The previous prime is 202120999991. The next prime is 202121000099. The reversal of 202121000021 is 120000121202.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 202121000021 - 2⁶ = 202120999957 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 202120999966 and 202121000011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202121000621) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3379901 + ... + 3439181.

It is an arithmetic number, because the mean of its divisors is an integer number (25399254336).

Almost surely, 2^202121000021 is an apocalyptic number.

It is an amenable number.

202121000021 is a deficient number, since it is larger than the sum of its proper divisors (1073034667).

202121000021 is a wasteful number, since it uses less digits than its factorization.

202121000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77323.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 202121000021 its reverse (120000121202), we get a palindrome (322121121223).

The spelling of 202121000021 in words is "two hundred two billion, one hundred twenty-one million, twenty-one", and thus it is an aban number.