127491866 has 4 divisors (see below), whose sum is σ = 191237802. Its totient is φ = 63745932.

The previous prime is 127491863. The next prime is 127491883. The reversal of 127491866 is 668194721.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 668194721 = 401 ⋅1666321.

It can be written as a sum of positive squares in only one way, i.e., 125328025 + 2163841 = 11195^2 + 1471^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (127491863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31872965 + ... + 31872968.

Almost surely, 2^127491866 is an apocalyptic number.

127491866 is a deficient number, since it is larger than the sum of its proper divisors (63745936).

127491866 is an equidigital number, since it uses as much as digits as its factorization.

127491866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63745935.

The product of its digits is 145152, while the sum is 44.

The square root of 127491866 is about 11291.2296053176. The cubic root of 127491866 is about 503.3006514556.

The spelling of 127491866 in words is "one hundred twenty-seven million, four hundred ninety-one thousand, eight hundred sixty-six".