51355391937 has 4 divisors (see below), whose sum is σ = 68473855920. Its totient is φ = 34236927956.

The previous prime is 51355391933. The next prime is 51355391959. The reversal of 51355391937 is 73919355315.

51355391937 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51355391937 - 2² = 51355391933 is a prime.

It is a super-2 number, since 2×51355391937² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51355391937.

It is not an unprimeable number, because it can be changed into a prime (51355391933) 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, 8559231987 + ... + 8559231992.

It is an arithmetic number, because the mean of its divisors is an integer number (17118463980).

Almost surely, 2^51355391937 is an apocalyptic number.

It is an amenable number.

51355391937 is a deficient number, since it is larger than the sum of its proper divisors (17118463983).

51355391937 is a wasteful number, since it uses less digits than its factorization.

51355391937 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17118463982.

The product of its digits is 1913625, while the sum is 51.

The spelling of 51355391937 in words is "fifty-one billion, three hundred fifty-five million, three hundred ninety-one thousand, nine hundred thirty-seven".