221001210112021 has 4 divisors (see below), whose sum is σ = 225171044265132. Its totient is φ = 216831375958912.

The previous prime is 221001210112019. The next prime is 221001210112049. The reversal of 221001210112021 is 120211012100122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 157182361743121 + 63818848368900 = 12537239^2 + 7988670^2 .

It is a cyclic number.

It is not a de Polignac number, because 221001210112021 - 2¹ = 221001210112019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221001210111986 and 221001210112004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221001217112021) 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, 2084917076476 + ... + 2084917076581.

It is an arithmetic number, because the mean of its divisors is an integer number (56292761066283).

Almost surely, 2^{221001210112021} is an apocalyptic number.

It is an amenable number.

221001210112021 is a deficient number, since it is larger than the sum of its proper divisors (4169834153111).

221001210112021 is an equidigital number, since it uses as much as digits as its factorization.

221001210112021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4169834153110.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 221001210112021 its reverse (120211012100122), we get a palindrome (341212222212143).

The spelling of 221001210112021 in words is "two hundred twenty-one trillion, one billion, two hundred ten million, one hundred twelve thousand, twenty-one".