251421373345 has 4 divisors (see below), whose sum is σ = 301705648020. Its totient is φ = 201137098672.

The previous prime is 251421373309. The next prime is 251421373349. The reversal of 251421373345 is 543373124152.

251421373345 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 72004745569 + 179416627776 = 268337^2 + 423576^2 .

It is a cyclic number.

It is not a de Polignac number, because 251421373345 - 2⁹ = 251421372833 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 251421373298 and 251421373307.

It is not an unprimeable number, because it can be changed into a prime (251421373349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25142137330 + ... + 25142137339.

It is an arithmetic number, because the mean of its divisors is an integer number (75426412005).

Almost surely, 2^251421373345 is an apocalyptic number.

It is an amenable number.

251421373345 is a deficient number, since it is larger than the sum of its proper divisors (50284274675).

251421373345 is an equidigital number, since it uses as much as digits as its factorization.

251421373345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50284274674.

The product of its digits is 302400, while the sum is 40.

Adding to 251421373345 its reverse (543373124152), we get a palindrome (794794497497).

The spelling of 251421373345 in words is "two hundred fifty-one billion, four hundred twenty-one million, three hundred seventy-three thousand, three hundred forty-five".