21066530739 has 4 divisors (see below), whose sum is σ = 28088707656. Its totient is φ = 14044353824.

The previous prime is 21066530729. The next prime is 21066530741. The reversal of 21066530739 is 93703566012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21066530739 - 2⁸ = 21066530483 is a prime.

It is a super-2 number, since 2×21066530739² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21066530739.

It is not an unprimeable number, because it can be changed into a prime (21066530729) 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, 3511088454 + ... + 3511088459.

It is an arithmetic number, because the mean of its divisors is an integer number (7022176914).

Almost surely, 2^21066530739 is an apocalyptic number.

21066530739 is a deficient number, since it is larger than the sum of its proper divisors (7022176917).

21066530739 is an equidigital number, since it uses as much as digits as its factorization.

21066530739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7022176916.

The product of its (nonzero) digits is 204120, while the sum is 42.

The spelling of 21066530739 in words is "twenty-one billion, sixty-six million, five hundred thirty thousand, seven hundred thirty-nine".