21701789 has 8 divisors (see below), whose sum is σ = 22097088. Its totient is φ = 21309120.

The previous prime is 21701749. The next prime is 21701803. The reversal of 21701789 is 98710712.

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 21701789 - 2²⁴ = 4924573 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21701749) 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, 23474 + ... + 24380.

It is an arithmetic number, because the mean of its divisors is an integer number (2762136).

Almost surely, 2^21701789 is an apocalyptic number.

It is an amenable number.

21701789 is a deficient number, since it is larger than the sum of its proper divisors (395299).

21701789 is an equidigital number, since it uses as much as digits as its factorization.

21701789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1315.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 21701789 is about 4658.5178973575. The cubic root of 21701789 is about 278.9321100814.

The spelling of 21701789 in words is "twenty-one million, seven hundred one thousand, seven hundred eighty-nine".