251640341 has 4 divisors (see below), whose sum is σ = 266442732. Its totient is φ = 236837952.

The previous prime is 251640317. The next prime is 251640349. The reversal of 251640341 is 143046152.

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 144600625 + 107039716 = 12025^2 + 10346^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-251640341 is a prime.

It is a super-2 number, since 2×251640341² = 126645722437192562, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 251640341.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251640349) 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, 7401170 + ... + 7401203.

It is an arithmetic number, because the mean of its divisors is an integer number (66610683).

Almost surely, 2^251640341 is an apocalyptic number.

It is an amenable number.

251640341 is a deficient number, since it is larger than the sum of its proper divisors (14802391).

251640341 is a wasteful number, since it uses less digits than its factorization.

251640341 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14802390.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 251640341 is about 15863.1756278496. The cubic root of 251640341 is about 631.3353225714.

Adding to 251640341 its reverse (143046152), we get a palindrome (394686493).

The spelling of 251640341 in words is "two hundred fifty-one million, six hundred forty thousand, three hundred forty-one".