257530991918 has 4 divisors (see below), whose sum is σ = 386296487880. Its totient is φ = 128765495958.

The previous prime is 257530991917. The next prime is 257530991969. The reversal of 257530991918 is 819199035752.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257530991917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64382747978 + ... + 64382747981.

It is an arithmetic number, because the mean of its divisors is an integer number (96574121970).

Almost surely, 2^257530991918 is an apocalyptic number.

257530991918 is a deficient number, since it is larger than the sum of its proper divisors (128765495962).

257530991918 is a wasteful number, since it uses less digits than its factorization.

257530991918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128765495961.

The product of its (nonzero) digits is 6123600, while the sum is 59.

The spelling of 257530991918 in words is "two hundred fifty-seven billion, five hundred thirty million, nine hundred ninety-one thousand, nine hundred eighteen".