21478741800689 has 4 divisors (see below), whose sum is σ = 21479729850480. Its totient is φ = 21477753750900.

The previous prime is 21478741800671. The next prime is 21478741800781. The reversal of 21478741800689 is 98600814787412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21478741800689 - 2⁸ = 21478741800433 is a prime.

It is a super-2 number, since 2×21478741800689² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21478741800619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 493992287 + ... + 494035764.

It is an arithmetic number, because the mean of its divisors is an integer number (5369932462620).

Almost surely, 2^{21478741800689} is an apocalyptic number.

It is an amenable number.

21478741800689 is a deficient number, since it is larger than the sum of its proper divisors (988049791).

21478741800689 is an equidigital number, since it uses as much as digits as its factorization.

21478741800689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 988049790.

The product of its (nonzero) digits is 43352064, while the sum is 65.

The spelling of 21478741800689 in words is "twenty-one trillion, four hundred seventy-eight billion, seven hundred forty-one million, eight hundred thousand, six hundred eighty-nine".