21190689 has 24 divisors (see below), whose sum is σ = 33225920. Its totient is φ = 12936672.

The previous prime is 21190679. The next prime is 21190703. The reversal of 21190689 is 98609112.

It is not a de Polignac number, because 21190689 - 2¹⁵ = 21157921 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21190679) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15612 + ... + 16914.

Almost surely, 2^21190689 is an apocalyptic number.

It is an amenable number.

21190689 is a deficient number, since it is larger than the sum of its proper divisors (12035231).

21190689 is a wasteful number, since it uses less digits than its factorization.

21190689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1461 (or 1458 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 21190689 is about 4603.3345522567. The cubic root of 21190689 is about 276.7249765004.

The spelling of 21190689 in words is "twenty-one million, one hundred ninety thousand, six hundred eighty-nine".