251155314545 has 4 divisors (see below), whose sum is σ = 301386377460. Its totient is φ = 200924251632.

The previous prime is 251155314517. The next prime is 251155314547. The reversal of 251155314545 is 545413551152.

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 135984675121 + 115170639424 = 368761^2 + 339368^2 .

It is a cyclic number.

It is not a de Polignac number, because 251155314545 - 2¹⁴ = 251155298161 is a prime.

It is not an unprimeable number, because it can be changed into a prime (251155314547) 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, 25115531450 + ... + 25115531459.

It is an arithmetic number, because the mean of its divisors is an integer number (75346594365).

Almost surely, 2^251155314545 is an apocalyptic number.

It is an amenable number.

251155314545 is a deficient number, since it is larger than the sum of its proper divisors (50231062915).

251155314545 is an equidigital number, since it uses as much as digits as its factorization.

251155314545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50231062914.

The product of its digits is 300000, while the sum is 41.

Adding to 251155314545 its reverse (545413551152), we get a palindrome (796568865697).

The spelling of 251155314545 in words is "two hundred fifty-one billion, one hundred fifty-five million, three hundred fourteen thousand, five hundred forty-five".