21365256700766 has 8 divisors (see below), whose sum is σ = 34961329146744. Its totient is φ = 9711480318520.

The previous prime is 21365256700751. The next prime is 21365256700819. The reversal of 21365256700766 is 66700765256312.

It is a happy number.

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

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, 485574015905 + ... + 485574015948.

It is an arithmetic number, because the mean of its divisors is an integer number (4370166143343).

Almost surely, 2^{21365256700766} is an apocalyptic number.

21365256700766 is a deficient number, since it is larger than the sum of its proper divisors (13596072445978).

21365256700766 is a wasteful number, since it uses less digits than its factorization.

21365256700766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 971148031866.

The product of its (nonzero) digits is 19051200, while the sum is 56.

It can be divided in two parts, 21365256 and 700766, that added together give a palindrome (22066022).

The spelling of 21365256700766 in words is "twenty-one trillion, three hundred sixty-five billion, two hundred fifty-six million, seven hundred thousand, seven hundred sixty-six".