21086757977289 has 4 divisors (see below), whose sum is σ = 28115677303056. Its totient is φ = 14057838651524.

The previous prime is 21086757977269. The next prime is 21086757977381. The reversal of 21086757977289 is 98277975768012.

It is a happy number.

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 21086757977289 - 2⁹ = 21086757976777 is a prime.

It is a super-2 number, since 2×21086757977289² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21086757977249) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3514459662879 + ... + 3514459662884.

It is an arithmetic number, because the mean of its divisors is an integer number (7028919325764).

Almost surely, 2^{21086757977289} is an apocalyptic number.

It is an amenable number.

21086757977289 is a deficient number, since it is larger than the sum of its proper divisors (7028919325767).

21086757977289 is an equidigital number, since it uses as much as digits as its factorization.

21086757977289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7028919325766.

The product of its (nonzero) digits is 1493614080, while the sum is 78.

The spelling of 21086757977289 in words is "twenty-one trillion, eighty-six billion, seven hundred fifty-seven million, nine hundred seventy-seven thousand, two hundred eighty-nine".