70128639 has 64 divisors (see below), whose sum is σ = 127488000. Its totient is φ = 37208160.

The previous prime is 70128629. The next prime is 70128659. The reversal of 70128639 is 93682107.

70128639 is a `hidden beast` number, since 7 + 0 + 12 + 8 + 639 = 666.

It is not a de Polignac number, because 70128639 - 2¹⁷ = 69997567 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70128629) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 211704 + ... + 212034.

It is an arithmetic number, because the mean of its divisors is an integer number (1992000).

Almost surely, 2^70128639 is an apocalyptic number.

70128639 is a deficient number, since it is larger than the sum of its proper divisors (57359361).

70128639 is a wasteful number, since it uses less digits than its factorization.

70128639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425 (or 419 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 70128639 is about 8374.2843873372. The cubic root of 70128639 is about 412.3808316921.

It can be divided in two parts, 7012 and 8639, that added together give a palindrome (15651).

The spelling of 70128639 in words is "seventy million, one hundred twenty-eight thousand, six hundred thirty-nine".