221101010021 has 4 divisors (see below), whose sum is σ = 221130314112. Its totient is φ = 221071705932.

The previous prime is 221101010017. The next prime is 221101010087. The reversal of 221101010021 is 120010101122.

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 not a de Polignac number, because 221101010021 - 2² = 221101010017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221101009984 and 221101010011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221101010321) 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, 14640725 + ... + 14655818.

It is an arithmetic number, because the mean of its divisors is an integer number (55282578528).

Almost surely, 2^221101010021 is an apocalyptic number.

It is an amenable number.

221101010021 is a deficient number, since it is larger than the sum of its proper divisors (29304091).

221101010021 is an equidigital number, since it uses as much as digits as its factorization.

221101010021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29304090.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 221101010021 its reverse (120010101122), we get a palindrome (341111111143).

The spelling of 221101010021 in words is "two hundred twenty-one billion, one hundred one million, ten thousand, twenty-one".