1221012111 has 8 divisors (see below), whose sum is σ = 1776017664. Its totient is φ = 740007320.

The previous prime is 1221012083. The next prime is 1221012119. The reversal of 1221012111 is 1112101221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221012111 - 2²¹ = 1218914959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221012119) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18500151 + ... + 18500216.

It is an arithmetic number, because the mean of its divisors is an integer number (222002208).

Almost surely, 2^1221012111 is an apocalyptic number.

1221012111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1221012111 is a deficient number, since it is larger than the sum of its proper divisors (555005553).

1221012111 is a wasteful number, since it uses less digits than its factorization.

1221012111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37000381.

The product of its (nonzero) digits is 8, while the sum is 12.

The square root of 1221012111 is about 34942.9837163342. The cubic root of 1221012111 is about 1068.8251322716.

Adding to 1221012111 its reverse (1112101221), we get a palindrome (2333113332).

The spelling of 1221012111 in words is "one billion, two hundred twenty-one million, twelve thousand, one hundred eleven".