51340255921 has 4 divisors (see below), whose sum is σ = 52043547172. Its totient is φ = 50636964672.

The previous prime is 51340255919. The next prime is 51340255951. The reversal of 51340255921 is 12955204315.

51340255921 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.

It can be written as a sum of positive squares in 2 ways, for example, as 14433619600 + 36906636321 = 120140^2 + 192111^2 .

It is a cyclic number.

It is not a de Polignac number, because 51340255921 - 2¹ = 51340255919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51340255951) 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, 351645516 + ... + 351645661.

It is an arithmetic number, because the mean of its divisors is an integer number (13010886793).

Almost surely, 2^51340255921 is an apocalyptic number.

It is an amenable number.

51340255921 is a deficient number, since it is larger than the sum of its proper divisors (703291251).

51340255921 is an equidigital number, since it uses as much as digits as its factorization.

51340255921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703291250.

The product of its (nonzero) digits is 54000, while the sum is 37.

The spelling of 51340255921 in words is "fifty-one billion, three hundred forty million, two hundred fifty-five thousand, nine hundred twenty-one".