21651421022606 has 8 divisors (see below), whose sum is σ = 34186454246280. Its totient is φ = 10255936273848.

The previous prime is 21651421022597. The next prime is 21651421022653. The reversal of 21651421022606 is 60622012415612.

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

It is a Harshad number since it is a multiple of its sum of digits (38), and also a Moran number because the ratio is a prime number: 569774237437 = 21651421022606 / (2 + 1 + 6 + 5 + 1 + 4 + 2 + 1 + 0 + 2 + 2 + 6 + 0 + 6).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21651421022606.

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, 284887118681 + ... + 284887118756.

It is an arithmetic number, because the mean of its divisors is an integer number (4273306780785).

Almost surely, 2^{21651421022606} is an apocalyptic number.

21651421022606 is a deficient number, since it is larger than the sum of its proper divisors (12535033223674).

21651421022606 is a wasteful number, since it uses less digits than its factorization.

21651421022606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569774237458.

The product of its (nonzero) digits is 69120, while the sum is 38.

The spelling of 21651421022606 in words is "twenty-one trillion, six hundred fifty-one billion, four hundred twenty-one million, twenty-two thousand, six hundred six".