27399187729 has 3 divisors (see below), whose sum is σ = 27399353257. Its totient is φ = 27399022202.

The previous prime is 27399187721. The next prime is 27399187769. The reversal of 27399187729 is 92778199372.

The square root of 27399187729 is 165527.

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 is not a de Polignac number, because 27399187729 - 2³ = 27399187721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27399187721) 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, 82764 + ... + 248290.

Almost surely, 2^27399187729 is an apocalyptic number.

27399187729 is the 165527-th square number.

27399187729 is the 82764-th centered octagonal number.

It is an amenable number.

27399187729 is a deficient number, since it is larger than the sum of its proper divisors (165528).

27399187729 is an frugal number, since it uses more digits than its factorization.

27399187729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331054 (or 165527 counting only the distinct ones).

The product of its digits is 24004512, while the sum is 64.

Multiplying 27399187729 by its sum of digits (64), we get a square (1753548014656 = 1324216²).

The spelling of 27399187729 in words is "twenty-seven billion, three hundred ninety-nine million, one hundred eighty-seven thousand, seven hundred twenty-nine".