257136423 has 4 divisors (see below), whose sum is σ = 342848568. Its totient is φ = 171424280.

The previous prime is 257136403. The next prime is 257136437. The reversal of 257136423 is 324631752.

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

It is a cyclic number.

It is not a de Polignac number, because 257136423 - 2¹⁸ = 256874279 is a prime.

It is a super-2 number, since 2×257136423² = 132238280066469858, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257136403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42856068 + ... + 42856073.

It is an arithmetic number, because the mean of its divisors is an integer number (85712142).

Almost surely, 2^257136423 is an apocalyptic number.

257136423 is a deficient number, since it is larger than the sum of its proper divisors (85712145).

257136423 is an equidigital number, since it uses as much as digits as its factorization.

257136423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85712144.

The product of its digits is 30240, while the sum is 33.

The square root of 257136423 is about 16035.4738938392. The cubic root of 257136423 is about 635.8985959330.

The spelling of 257136423 in words is "two hundred fifty-seven million, one hundred thirty-six thousand, four hundred twenty-three".