111212021999 has 32 divisors (see below), whose sum is σ = 129942134784. Its totient is φ = 94239936000.

The previous prime is 111212021989. The next prime is 111212022017. The reversal of 111212021999 is 999120212111.

It is a cyclic number.

It is not a de Polignac number, because 111212021999 - 2⁸ = 111212021743 is a prime.

It is a super-2 number, since 2×111212021999² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111212021929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7128962 + ... + 7144544.

It is an arithmetic number, because the mean of its divisors is an integer number (4060691712).

Almost surely, 2^111212021999 is an apocalyptic number.

111212021999 is a deficient number, since it is larger than the sum of its proper divisors (18730112785).

111212021999 is a wasteful number, since it uses less digits than its factorization.

111212021999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16407.

The product of its (nonzero) digits is 5832, while the sum is 38.

The spelling of 111212021999 in words is "one hundred eleven billion, two hundred twelve million, twenty-one thousand, nine hundred ninety-nine".