127640638 has 4 divisors (see below), whose sum is σ = 191460960. Its totient is φ = 63820318.

The previous prime is 127640627. The next prime is 127640677. The reversal of 127640638 is 836046721.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 127640597 and 127640606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31910158 + ... + 31910161.

It is an arithmetic number, because the mean of its divisors is an integer number (47865240).

Almost surely, 2^127640638 is an apocalyptic number.

127640638 is a deficient number, since it is larger than the sum of its proper divisors (63820322).

127640638 is an equidigital number, since it uses as much as digits as its factorization.

127640638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63820321.

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 127640638 is about 11297.8156295808. The cubic root of 127640638 is about 503.4963448247.

It can be divided in two parts, 1276 and 40638, that added together give a palindrome (41914).

The spelling of 127640638 in words is "one hundred twenty-seven million, six hundred forty thousand, six hundred thirty-eight".