21662312212661 has 8 divisors (see below), whose sum is σ = 22071640571424. Its totient is φ = 21253006279440.

The previous prime is 21662312212633. The next prime is 21662312212669. The reversal of 21662312212661 is 16621221326612.

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

It is a de Polignac number, because none of the positive numbers 2^k-21662312212661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21662312212669) 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, 3649811 + ... + 7526336.

It is an arithmetic number, because the mean of its divisors is an integer number (2758955071428).

Almost surely, 2^{21662312212661} is an apocalyptic number.

It is an amenable number.

21662312212661 is a deficient number, since it is larger than the sum of its proper divisors (409328358763).

21662312212661 is a wasteful number, since it uses less digits than its factorization.

21662312212661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11212771.

The product of its digits is 124416, while the sum is 41.

The spelling of 21662312212661 in words is "twenty-one trillion, six hundred sixty-two billion, three hundred twelve million, two hundred twelve thousand, six hundred sixty-one".