221212021201 has 4 divisors (see below), whose sum is σ = 221252195952. Its totient is φ = 221171846452.

The previous prime is 221212021157. The next prime is 221212021231. The reversal of 221212021201 is 102120212122.

It is a happy number.

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 221212021201 - 2¹⁵ = 221211988433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221212021231) 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, 20079115 + ... + 20090128.

It is an arithmetic number, because the mean of its divisors is an integer number (55313048988).

Almost surely, 2^221212021201 is an apocalyptic number.

It is an amenable number.

221212021201 is a deficient number, since it is larger than the sum of its proper divisors (40174751).

221212021201 is an equidigital number, since it uses as much as digits as its factorization.

221212021201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40174750.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 221212021201 its reverse (102120212122), we get a palindrome (323332233323).

The spelling of 221212021201 in words is "two hundred twenty-one billion, two hundred twelve million, twenty-one thousand, two hundred one".