21277379117 has 4 divisors (see below), whose sum is σ = 21472584540. Its totient is φ = 21082173696.

The previous prime is 21277379113. The next prime is 21277379171. The reversal of 21277379117 is 71197377212.

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

It can be written as a sum of positive squares in 2 ways, for example, as 10214336356 + 11063042761 = 101066^2 + 105181^2 .

It is a cyclic number.

It is not a de Polignac number, because 21277379117 - 2² = 21277379113 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21277379113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97602548 + ... + 97602765.

It is an arithmetic number, because the mean of its divisors is an integer number (5368146135).

Almost surely, 2^21277379117 is an apocalyptic number.

It is an amenable number.

21277379117 is a deficient number, since it is larger than the sum of its proper divisors (195205423).

21277379117 is a wasteful number, since it uses less digits than its factorization.

21277379117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195205422.

The product of its digits is 259308, while the sum is 47.

The spelling of 21277379117 in words is "twenty-one billion, two hundred seventy-seven million, three hundred seventy-nine thousand, one hundred seventeen".