51280203721 has 4 divisors (see below), whose sum is σ = 51399183744. Its totient is φ = 51161223700.

The previous prime is 51280203719. The next prime is 51280203743. The reversal of 51280203721 is 12730208215.

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 51280203721 - 2¹ = 51280203719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51280233721) 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, 59489365 + ... + 59490226.

It is an arithmetic number, because the mean of its divisors is an integer number (12849795936).

Almost surely, 2^51280203721 is an apocalyptic number.

It is an amenable number.

51280203721 is a deficient number, since it is larger than the sum of its proper divisors (118980023).

51280203721 is a wasteful number, since it uses less digits than its factorization.

51280203721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118980022.

The product of its (nonzero) digits is 6720, while the sum is 31.

The spelling of 51280203721 in words is "fifty-one billion, two hundred eighty million, two hundred three thousand, seven hundred twenty-one".