127857661 has 4 divisors (see below), whose sum is σ = 130024800. Its totient is φ = 125690524.

The previous prime is 127857649. The next prime is 127857673. The reversal of 127857661 is 166758721.

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 an interprime number because it is at equal distance from previous prime (127857649) and next prime (127857673).

It is a cyclic number.

It is not a de Polignac number, because 127857661 - 2¹⁹ = 127333373 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 (127857601) 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, 1083481 + ... + 1083598.

It is an arithmetic number, because the mean of its divisors is an integer number (32506200).

Almost surely, 2^127857661 is an apocalyptic number.

It is an amenable number.

127857661 is a deficient number, since it is larger than the sum of its proper divisors (2167139).

127857661 is an equidigital number, since it uses as much as digits as its factorization.

127857661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2167138.

The product of its digits is 141120, while the sum is 43.

The square root of 127857661 is about 11307.4161946928. The cubic root of 127857661 is about 503.7815424385.

The spelling of 127857661 in words is "one hundred twenty-seven million, eight hundred fifty-seven thousand, six hundred sixty-one".