21960689 has 8 divisors (see below), whose sum is σ = 22283688. Its totient is φ = 21640320.

The previous prime is 21960683. The next prime is 21960727. The reversal of 21960689 is 98606912.

It can be written as a sum of positive squares in 4 ways, for example, as 2890000 + 19070689 = 1700^2 + 4367^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21960689 - 2²⁰ = 20912113 is a prime.

It is a super-2 number, since 2×21960689² = 964543722709442, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21960683) 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, 20999 + ... + 22019.

It is an arithmetic number, because the mean of its divisors is an integer number (2785461).

Almost surely, 2^21960689 is an apocalyptic number.

It is an amenable number.

21960689 is a deficient number, since it is larger than the sum of its proper divisors (322999).

21960689 is a wasteful number, since it uses less digits than its factorization.

21960689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1315.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 21960689 is about 4686.2233194759. The cubic root of 21960689 is about 280.0369381540.

It can be divided in two parts, 2 and 1960689, that added together give a palindrome (1960691).

The spelling of 21960689 in words is "twenty-one million, nine hundred sixty thousand, six hundred eighty-nine".