221121210202111 has 4 divisors (see below), whose sum is σ = 223605718182000. Its totient is φ = 218636702222224.

The previous prime is 221121210202099. The next prime is 221121210202117. The reversal of 221121210202111 is 111202012121122.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221121210202111 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 (221121210202117) 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, 1242253989811 + ... + 1242253989988.

It is an arithmetic number, because the mean of its divisors is an integer number (55901429545500).

Almost surely, 2^{221121210202111} is an apocalyptic number.

221121210202111 is a deficient number, since it is larger than the sum of its proper divisors (2484507979889).

221121210202111 is an equidigital number, since it uses as much as digits as its factorization.

221121210202111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2484507979888.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 221121210202111 its reverse (111202012121122), we get a palindrome (332323222323233).

The spelling of 221121210202111 in words is "two hundred twenty-one trillion, one hundred twenty-one billion, two hundred ten million, two hundred two thousand, one hundred eleven".