211221221112111 has 32 divisors (see below), whose sum is σ = 327742007819776. Its totient is φ = 118499743152000.

The previous prime is 211221221111993. The next prime is 211221221112119. The reversal of 211221221112111 is 111211122122112.

211221221112111 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 211221221112111 - 2²¹ = 211221219014959 is a prime.

It is a super-2 number, since 2×211221221112111² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211221221112119) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 151698625 + ... + 153084666.

It is an arithmetic number, because the mean of its divisors is an integer number (10241937744368).

Almost surely, 2^{211221221112111} is an apocalyptic number.

211221221112111 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

211221221112111 is a deficient number, since it is larger than the sum of its proper divisors (116520786707665).

211221221112111 is a wasteful number, since it uses less digits than its factorization.

211221221112111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304783903.

The product of its digits is 64, while the sum is 21.

Adding to 211221221112111 its reverse (111211122122112), we get a palindrome (322432343234223).

The spelling of 211221221112111 in words is "two hundred eleven trillion, two hundred twenty-one billion, two hundred twenty-one million, one hundred twelve thousand, one hundred eleven".