221021000112021 has 4 divisors (see below), whose sum is σ = 294694666816032. Its totient is φ = 147347333408012.

The previous prime is 221021000112001. The next prime is 221021000112079. The reversal of 221021000112021 is 120211000120122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221021000112021 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221021000112001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36836833352001 + ... + 36836833352006.

It is an arithmetic number, because the mean of its divisors is an integer number (73673666704008).

Almost surely, 2^{221021000112021} is an apocalyptic number.

It is an amenable number.

221021000112021 is a deficient number, since it is larger than the sum of its proper divisors (73673666704011).

221021000112021 is an equidigital number, since it uses as much as digits as its factorization.

221021000112021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73673666704010.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 221021000112021 its reverse (120211000120122), we get a palindrome (341232000232143).

The spelling of 221021000112021 in words is "two hundred twenty-one trillion, twenty-one billion, one hundred twelve thousand, twenty-one".