21395606 has 4 divisors (see below), whose sum is σ = 32093412. Its totient is φ = 10697802.

The previous prime is 21395603. The next prime is 21395617. The reversal of 21395606 is 60659312.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×21395606² = 915543912214472, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21395603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5348900 + ... + 5348903.

It is an arithmetic number, because the mean of its divisors is an integer number (8023353).

Almost surely, 2^21395606 is an apocalyptic number.

21395606 is a deficient number, since it is larger than the sum of its proper divisors (10697806).

21395606 is a wasteful number, since it uses less digits than its factorization.

21395606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10697805.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 21395606 is about 4625.5384551423. The cubic root of 21395606 is about 277.6141066865.

The spelling of 21395606 in words is "twenty-one million, three hundred ninety-five thousand, six hundred six".