12000021989 has 4 divisors (see below), whose sum is σ = 12005790540. Its totient is φ = 11994253440.

The previous prime is 12000021961. The next prime is 12000022031. The reversal of 12000021989 is 98912000021.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2387788225 + 9612233764 = 48865^2 + 98042^2 .

It is a cyclic number.

It is not a de Polignac number, because 12000021989 - 2¹⁶ = 11999956453 is a prime.

It is a super-2 number, since 2×12000021989² (a number of 21 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 (12000021289) 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, 2881154 + ... + 2885315.

It is an arithmetic number, because the mean of its divisors is an integer number (3001447635).

Almost surely, 2^12000021989 is an apocalyptic number.

It is an amenable number.

12000021989 is a deficient number, since it is larger than the sum of its proper divisors (5768551).

12000021989 is an equidigital number, since it uses as much as digits as its factorization.

12000021989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5768550.

The product of its (nonzero) digits is 2592, while the sum is 32.

The spelling of 12000021989 in words is "twelve billion, twenty-one thousand, nine hundred eighty-nine".