257861855601 has 27 divisors (see below), whose sum is σ = 433296002763. Its totient is φ = 147343538160.

The previous prime is 257861855551. The next prime is 257861855653. The reversal of 257861855601 is 106558168752.

The square root of 257861855601 is 507801.

It is a perfect power (a square), and thus also a powerful number.

257861855601 is a `hidden beast` number, since 2 + 5 + 7 + 86 + 1 + 8 + 556 + 0 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 191142965601 + 66718890000 = 437199^2 + 258300^2 .

It is not a de Polignac number, because 257861855601 - 2¹¹ = 257861853553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (257861855681) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 10651731 + ... + 10675911.

Almost surely, 2^257861855601 is an apocalyptic number.

257861855601 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

257861855601 is the 507801-st square number.

257861855601 is the 253901-st centered octagonal number.

It is an amenable number.

257861855601 is a deficient number, since it is larger than the sum of its proper divisors (175434147162).

257861855601 is an frugal number, since it uses more digits than its factorization.

257861855601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48382 (or 24191 counting only the distinct ones).

The product of its (nonzero) digits is 4032000, while the sum is 54.

The spelling of 257861855601 in words is "two hundred fifty-seven billion, eight hundred sixty-one million, eight hundred fifty-five thousand, six hundred one".