27994978489 has 3 divisors (see below), whose sum is σ = 27995145807. Its totient is φ = 27994811172.

The previous prime is 27994978483. The next prime is 27994978493. The reversal of 27994978489 is 98487949972.

The square root of 27994978489 is 167317.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 27970890025 + 24088464 = 167245^2 + 4908^2 .

It is not a de Polignac number, because 27994978489 - 2³ = 27994978481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27994978481) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 83659 + ... + 250975.

It is an arithmetic number, because the mean of its divisors is an integer number (9331715269).

Almost surely, 2^27994978489 is an apocalyptic number.

27994978489 is the 167317-th square number.

27994978489 is the 83659-th centered octagonal number.

It is an amenable number.

27994978489 is a deficient number, since it is larger than the sum of its proper divisors (167318).

27994978489 is an frugal number, since it uses more digits than its factorization.

27994978489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334634 (or 167317 counting only the distinct ones).

The product of its digits is 658409472, while the sum is 76.

The spelling of 27994978489 in words is "twenty-seven billion, nine hundred ninety-four million, nine hundred seventy-eight thousand, four hundred eighty-nine".