221020212011111 has 4 divisors (see below), whose sum is σ = 221603378797800. Its totient is φ = 220437045224424.

The previous prime is 221020212011089. The next prime is 221020212011119. The reversal of 221020212011111 is 111110212020122.

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

It is a cyclic number.

It is not a de Polignac number, because 221020212011111 - 2⁶ = 221020212011047 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221020212011111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221020212011119) 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, 291583392776 + ... + 291583393533.

It is an arithmetic number, because the mean of its divisors is an integer number (55400844699450).

Almost surely, 2^{221020212011111} is an apocalyptic number.

221020212011111 is a deficient number, since it is larger than the sum of its proper divisors (583166786689).

221020212011111 is an equidigital number, since it uses as much as digits as its factorization.

221020212011111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 583166786688.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 221020212011111 its reverse (111110212020122), we get a palindrome (332130424031233).

The spelling of 221020212011111 in words is "two hundred twenty-one trillion, twenty billion, two hundred twelve million, eleven thousand, one hundred eleven".