128638629 has 48 divisors (see below), whose sum is σ = 218504832. Its totient is φ = 71414784.

The previous prime is 128638621. The next prime is 128638637. The reversal of 128638629 is 926836821.

128638629 is a `hidden beast` number, since 1 + 2 + 8 + 638 + 6 + 2 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (128638621) and next prime (128638637).

It is not a de Polignac number, because 128638629 - 2³ = 128638621 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128638621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 381549 + ... + 381885.

It is an arithmetic number, because the mean of its divisors is an integer number (4552184).

Almost surely, 2^128638629 is an apocalyptic number.

It is an amenable number.

128638629 is a deficient number, since it is larger than the sum of its proper divisors (89866203).

128638629 is a wasteful number, since it uses less digits than its factorization.

128638629 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 506 (or 503 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 128638629 is about 11341.8970635428. The cubic root of 128638629 is about 504.8051779297.

The spelling of 128638629 in words is "one hundred twenty-eight million, six hundred thirty-eight thousand, six hundred twenty-nine".