21071697 has 8 divisors (see below), whose sum is σ = 28129056. Its totient is φ = 14031072.

The previous prime is 21071683. The next prime is 21071707. The reversal of 21071697 is 79617012.

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

It is not a de Polignac number, because 21071697 - 2¹¹ = 21069649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21071647) 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, 868 + ... + 6549.

It is an arithmetic number, because the mean of its divisors is an integer number (3516132).

Almost surely, 2^21071697 is an apocalyptic number.

It is an amenable number.

21071697 is a deficient number, since it is larger than the sum of its proper divisors (7057359).

21071697 is an equidigital number, since it uses as much as digits as its factorization.

21071697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8367.

The product of its (nonzero) digits is 5292, while the sum is 33.

The square root of 21071697 is about 4590.3918133423. The cubic root of 21071697 is about 276.2060397006.

The spelling of 21071697 in words is "twenty-one million, seventy-one thousand, six hundred ninety-seven".