27956138431 has 4 divisors (see below), whose sum is σ = 30106610632. Its totient is φ = 25805666232.

The previous prime is 27956138429. The next prime is 27956138449. The reversal of 27956138431 is 13483165972.

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

It is a cyclic number.

It is not a de Polignac number, because 27956138431 - 2¹ = 27956138429 is a prime.

It is a super-2 number, since 2×27956138431² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27956138401) 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, 1075236081 + ... + 1075236106.

It is an arithmetic number, because the mean of its divisors is an integer number (7526652658).

Almost surely, 2^27956138431 is an apocalyptic number.

27956138431 is a deficient number, since it is larger than the sum of its proper divisors (2150472201).

27956138431 is a wasteful number, since it uses less digits than its factorization.

27956138431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2150472200.

The product of its digits is 1088640, while the sum is 49.

The spelling of 27956138431 in words is "twenty-seven billion, nine hundred fifty-six million, one hundred thirty-eight thousand, four hundred thirty-one".