21456662606 has 8 divisors (see below), whose sum is σ = 32189698704. Its totient is φ = 10726763040.

The previous prime is 21456662569. The next prime is 21456662611. The reversal of 21456662606 is 60626665412.

It is a happy number.

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

It is a super-2 number, since 2×21456662606² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 766955 + ... + 794438.

It is an arithmetic number, because the mean of its divisors is an integer number (4023712338).

Almost surely, 2^21456662606 is an apocalyptic number.

21456662606 is a deficient number, since it is larger than the sum of its proper divisors (10733036098).

21456662606 is a wasteful number, since it uses less digits than its factorization.

21456662606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1568266.

The product of its (nonzero) digits is 622080, while the sum is 44.

The spelling of 21456662606 in words is "twenty-one billion, four hundred fifty-six million, six hundred sixty-two thousand, six hundred six".