161257557 has 8 divisors (see below), whose sum is σ = 215273376. Its totient is φ = 107373392.

The previous prime is 161257549. The next prime is 161257559. The reversal of 161257557 is 755752161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161257557 - 2³ = 161257549 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161257559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30018 + ... + 34979.

It is an arithmetic number, because the mean of its divisors is an integer number (26909172).

Almost surely, 2^161257557 is an apocalyptic number.

It is an amenable number.

161257557 is a deficient number, since it is larger than the sum of its proper divisors (54015819).

161257557 is an equidigital number, since it uses as much as digits as its factorization.

161257557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65827.

The product of its digits is 73500, while the sum is 39.

The square root of 161257557 is about 12698.7226522985. The cubic root of 161257557 is about 544.3021193882.

The spelling of 161257557 in words is "one hundred sixty-one million, two hundred fifty-seven thousand, five hundred fifty-seven".