21301989 has 8 divisors (see below), whose sum is σ = 28550592. Its totient is φ = 14127360.

The previous prime is 21301967. The next prime is 21301997. The reversal of 21301989 is 98910312.

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

It is not a de Polignac number, because 21301989 - 2⁵ = 21301957 is a prime.

It is a super-2 number, since 2×21301989² = 907549470712242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21301949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17817 + ... + 18974.

It is an arithmetic number, because the mean of its divisors is an integer number (3568824).

Almost surely, 2^21301989 is an apocalyptic number.

It is an amenable number.

21301989 is a deficient number, since it is larger than the sum of its proper divisors (7248603).

21301989 is a wasteful number, since it uses less digits than its factorization.

21301989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36987.

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 21301989 is about 4615.4077826342. The cubic root of 21301989 is about 277.2086122439.

The spelling of 21301989 in words is "twenty-one million, three hundred one thousand, nine hundred eighty-nine".