51131441643 has 4 divisors (see below), whose sum is σ = 68175255528. Its totient is φ = 34087627760.

The previous prime is 51131441629. The next prime is 51131441663. The reversal of 51131441643 is 34614413115.

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 51131441643 - 2⁹ = 51131441131 is a prime.

It is a super-3 number, since 3×51131441643³ (a number of 33 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (51131441623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8521906938 + ... + 8521906943.

It is an arithmetic number, because the mean of its divisors is an integer number (17043813882).

Almost surely, 2^51131441643 is an apocalyptic number.

51131441643 is a deficient number, since it is larger than the sum of its proper divisors (17043813885).

51131441643 is a wasteful number, since it uses less digits than its factorization.

51131441643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17043813884.

The product of its digits is 17280, while the sum is 33.

Adding to 51131441643 its reverse (34614413115), we get a palindrome (85745854758).

The spelling of 51131441643 in words is "fifty-one billion, one hundred thirty-one million, four hundred forty-one thousand, six hundred forty-three".