51675767021 has 4 divisors (see below), whose sum is σ = 51676428000. Its totient is φ = 51675106044.

The previous prime is 51675766997. The next prime is 51675767053. The reversal of 51675767021 is 12076757615.

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 a de Polignac number, because none of the positive numbers 2^k-51675767021 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 (51675767071) 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, 194591 + ... + 375788.

It is an arithmetic number, because the mean of its divisors is an integer number (12919107000).

Almost surely, 2^51675767021 is an apocalyptic number.

It is an amenable number.

51675767021 is a deficient number, since it is larger than the sum of its proper divisors (660979).

51675767021 is an equidigital number, since it uses as much as digits as its factorization.

51675767021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660978.

The product of its (nonzero) digits is 617400, while the sum is 47.

The spelling of 51675767021 in words is "fifty-one billion, six hundred seventy-five million, seven hundred sixty-seven thousand, twenty-one".