51395036421 has 4 divisors (see below), whose sum is σ = 68526715232. Its totient is φ = 34263357612.

The previous prime is 51395036383. The next prime is 51395036437. The reversal of 51395036421 is 12463059315.

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 not a de Polignac number, because 51395036421 - 2¹⁹ = 51394512133 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51395036421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51395036471) 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, 8565839401 + ... + 8565839406.

It is an arithmetic number, because the mean of its divisors is an integer number (17131678808).

Almost surely, 2^51395036421 is an apocalyptic number.

It is an amenable number.

51395036421 is a deficient number, since it is larger than the sum of its proper divisors (17131678811).

51395036421 is a wasteful number, since it uses less digits than its factorization.

51395036421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17131678810.

The product of its (nonzero) digits is 97200, while the sum is 39.

The spelling of 51395036421 in words is "fifty-one billion, three hundred ninety-five million, thirty-six thousand, four hundred twenty-one".