12021989 has 8 divisors (see below), whose sum is σ = 14032128. Its totient is φ = 10085040.

The previous prime is 12021973. The next prime is 12021991. The reversal of 12021989 is 98912021.

It is a happy number.

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

It is not a de Polignac number, because 12021989 - 2⁴ = 12021973 is a prime.

It is a super-2 number, since 2×12021989² = 289056439032242, which 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 (12021959) 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, 17942 + ... + 18599.

It is an arithmetic number, because the mean of its divisors is an integer number (1754016).

Almost surely, 2^12021989 is an apocalyptic number.

It is an amenable number.

12021989 is a deficient number, since it is larger than the sum of its proper divisors (2010139).

12021989 is an equidigital number, since it uses as much as digits as its factorization.

12021989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36595.

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

The square root of 12021989 is about 3467.2740012869. The cubic root of 12021989 is about 229.0826027465.

Adding to 12021989 its sum of digits (32), we get a palindrome (12022021).

The spelling of 12021989 in words is "twelve million, twenty-one thousand, nine hundred eighty-nine".