221212002222021 has 4 divisors (see below), whose sum is σ = 294949336296032. Its totient is φ = 147474668148012.

The previous prime is 221212002221933. The next prime is 221212002222023. The reversal of 221212002222021 is 120222200212122.

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 not a de Polignac number, because 221212002222021 - 2³⁸ = 220937124315077 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221212002222023) 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, 36868667037001 + ... + 36868667037006.

It is an arithmetic number, because the mean of its divisors is an integer number (73737334074008).

Almost surely, 2^{221212002222021} is an apocalyptic number.

It is an amenable number.

221212002222021 is a deficient number, since it is larger than the sum of its proper divisors (73737334074011).

221212002222021 is an equidigital number, since it uses as much as digits as its factorization.

221212002222021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73737334074010.

The product of its (nonzero) digits is 512, while the sum is 21.

Adding to 221212002222021 its reverse (120222200212122), we get a palindrome (341434202434143).

The spelling of 221212002222021 in words is "two hundred twenty-one trillion, two hundred twelve billion, two million, two hundred twenty-two thousand, twenty-one".