257136768 has 192 divisors, whose sum is σ = 877705920. Its totient is φ = 73405440.

The previous prime is 257136767. The next prime is 257136779. The reversal of 257136768 is 867631752.

257136768 is a `hidden beast` number, since 2 + 571 + 3 + 6 + 76 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

It is a super-2 number, since 2×257136768² = 132238634914971648, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (257136767) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 217138 + ... + 218318.

It is an arithmetic number, because the mean of its divisors is an integer number (4571385).

Almost surely, 2^257136768 is an apocalyptic number.

257136768 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 257136768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (438852960).

257136768 is an abundant number, since it is smaller than the sum of its proper divisors (620569152).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

257136768 is an equidigital number, since it uses as much as digits as its factorization.

257136768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1217 (or 1193 counting only the distinct ones).

The product of its digits is 423360, while the sum is 45.

The square root of 257136768 is about 16035.4846512352. The cubic root of 257136768 is about 635.8988803279.

The spelling of 257136768 in words is "two hundred fifty-seven million, one hundred thirty-six thousand, seven hundred sixty-eight".