21277425409 has 4 divisors (see below), whose sum is σ = 21533780016. Its totient is φ = 21021070804.

The previous prime is 21277425383. The next prime is 21277425439. The reversal of 21277425409 is 90452477212.

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 21277425409 - 2²⁷ = 21143207681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21277425439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128177179 + ... + 128177344.

It is an arithmetic number, because the mean of its divisors is an integer number (5383445004).

Almost surely, 2^21277425409 is an apocalyptic number.

It is an amenable number.

21277425409 is a deficient number, since it is larger than the sum of its proper divisors (256354607).

21277425409 is an equidigital number, since it uses as much as digits as its factorization.

21277425409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 256354606.

The product of its (nonzero) digits is 282240, while the sum is 43.

The spelling of 21277425409 in words is "twenty-one billion, two hundred seventy-seven million, four hundred twenty-five thousand, four hundred nine".