51548271991 has 16 divisors (see below), whose sum is σ = 53962546176. Its totient is φ = 49148643456.

The previous prime is 51548271953. The next prime is 51548272033. The reversal of 51548271991 is 19917284515.

It is a cyclic number.

It is not a de Polignac number, because 51548271991 - 2⁹ = 51548271479 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 (51548271091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17755446 + ... + 17758348.

It is an arithmetic number, because the mean of its divisors is an integer number (3372659136).

Almost surely, 2^51548271991 is an apocalyptic number.

51548271991 is a deficient number, since it is larger than the sum of its proper divisors (2414274185).

51548271991 is a wasteful number, since it uses less digits than its factorization.

51548271991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5142.

The product of its digits is 907200, while the sum is 52.

The spelling of 51548271991 in words is "fifty-one billion, five hundred forty-eight million, two hundred seventy-one thousand, nine hundred ninety-one".