9927879421 has 4 divisors (see below), whose sum is σ = 9939200572. Its totient is φ = 9916558272.

The previous prime is 9927879407. The next prime is 9927879443. The reversal of 9927879421 is 1249787299.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1249787299 = 191 ⋅6543389.

It can be written as a sum of positive squares in 2 ways, for example, as 7944156900 + 1983722521 = 89130^2 + 44539^2 .

It is a cyclic number.

It is not a de Polignac number, because 9927879421 - 2²³ = 9919490813 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 (9927879461) 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, 5659260 + ... + 5661013.

It is an arithmetic number, because the mean of its divisors is an integer number (2484800143).

Almost surely, 2^9927879421 is an apocalyptic number.

It is an amenable number.

9927879421 is a deficient number, since it is larger than the sum of its proper divisors (11321151).

9927879421 is a wasteful number, since it uses less digits than its factorization.

9927879421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11321150.

The product of its digits is 4572288, while the sum is 58.

The square root of 9927879421 is about 99638.7445775989. The cubic root of 9927879421 is about 2149.2428861840.

The spelling of 9927879421 in words is "nine billion, nine hundred twenty-seven million, eight hundred seventy-nine thousand, four hundred twenty-one".