257440537 has 4 divisors (see below), whose sum is σ = 272584116. Its totient is φ = 242296960.

The previous prime is 257440507. The next prime is 257440549. The reversal of 257440537 is 735044752.

It is a happy number.

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 145419481 + 112021056 = 12059^2 + 10584^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257440537 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 257440496 and 257440505.

It is not an unprimeable number, because it can be changed into a prime (257440507) 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, 7571764 + ... + 7571797.

It is an arithmetic number, because the mean of its divisors is an integer number (68146029).

Almost surely, 2^257440537 is an apocalyptic number.

It is an amenable number.

257440537 is a deficient number, since it is larger than the sum of its proper divisors (15143579).

257440537 is a wasteful number, since it uses less digits than its factorization.

257440537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15143578.

The product of its (nonzero) digits is 117600, while the sum is 37.

The square root of 257440537 is about 16044.9536303475. The cubic root of 257440537 is about 636.1491885621.

The spelling of 257440537 in words is "two hundred fifty-seven million, four hundred forty thousand, five hundred thirty-seven".