999991021000111 has 4 divisors (see below), whose sum is σ = 1142846881142992. Its totient is φ = 857135160857232.

The previous prime is 999991021000073. The next prime is 999991021000123. The reversal of 999991021000111 is 111000120199999.

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 999991021000111 - 2²⁷ = 999990886782383 is a prime.

It is a super-3 number, since 3×999991021000111³ (a number of 46 digits) contains 333 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 (999991021004111) 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, 71427930071430 + ... + 71427930071443.

It is an arithmetic number, because the mean of its divisors is an integer number (285711720285748).

Almost surely, 2^{999991021000111} is an apocalyptic number.

999991021000111 is a deficient number, since it is larger than the sum of its proper divisors (142855860142881).

999991021000111 is a wasteful number, since it uses less digits than its factorization.

999991021000111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142855860142880.

The product of its (nonzero) digits is 118098, while the sum is 52.

The spelling of 999991021000111 in words is "nine hundred ninety-nine trillion, nine hundred ninety-one billion, twenty-one million, one hundred eleven", and thus it is an aban number.