27905899421 has 8 divisors (see below), whose sum is σ = 28527334104. Its totient is φ = 27289753920.

The previous prime is 27905899409. The next prime is 27905899451. The reversal of 27905899421 is 12499850972.

It can be written as a sum of positive squares in 4 ways, for example, as 4731926521 + 23173972900 = 68789^2 + 152230^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27905899421 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 (27905899451) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1311626 + ... + 1332731.

It is an arithmetic number, because the mean of its divisors is an integer number (3565916763).

Almost surely, 2^27905899421 is an apocalyptic number.

It is an amenable number.

27905899421 is a deficient number, since it is larger than the sum of its proper divisors (621434683).

27905899421 is a wasteful number, since it uses less digits than its factorization.

27905899421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2644591.

The product of its (nonzero) digits is 3265920, while the sum is 56.

The spelling of 27905899421 in words is "twenty-seven billion, nine hundred five million, eight hundred ninety-nine thousand, four hundred twenty-one".