257727239661 has 4 divisors (see below), whose sum is σ = 343636319552. Its totient is φ = 171818159772.

The previous prime is 257727239633. The next prime is 257727239683. The reversal of 257727239661 is 166932727752.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 257727239661 - 2¹⁴ = 257727223277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257727439661) 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, 42954539941 + ... + 42954539946.

It is an arithmetic number, because the mean of its divisors is an integer number (85909079888).

Almost surely, 2^257727239661 is an apocalyptic number.

It is an amenable number.

257727239661 is a deficient number, since it is larger than the sum of its proper divisors (85909079891).

257727239661 is an equidigital number, since it uses as much as digits as its factorization.

257727239661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85909079890.

The product of its digits is 13335840, while the sum is 57.

The spelling of 257727239661 in words is "two hundred fifty-seven billion, seven hundred twenty-seven million, two hundred thirty-nine thousand, six hundred sixty-one".