51534263491 has 4 divisors (see below), whose sum is σ = 51534723184. Its totient is φ = 51533803800.

The previous prime is 51534263489. The next prime is 51534263513. The reversal of 51534263491 is 19436243515.

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 a cyclic number.

It is not a de Polignac number, because 51534263491 - 2¹ = 51534263489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51534263401) 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, 60946 + ... + 326776.

It is an arithmetic number, because the mean of its divisors is an integer number (12883680796).

Almost surely, 2^51534263491 is an apocalyptic number.

51534263491 is a deficient number, since it is larger than the sum of its proper divisors (459693).

51534263491 is a wasteful number, since it uses less digits than its factorization.

51534263491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 459692.

The product of its digits is 388800, while the sum is 43.

The spelling of 51534263491 in words is "fifty-one billion, five hundred thirty-four million, two hundred sixty-three thousand, four hundred ninety-one".