638085155 has 8 divisors (see below), whose sum is σ = 767120784. Its totient is φ = 509522400.

The previous prime is 638085139. The next prime is 638085169. The reversal of 638085155 is 551580836.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 638085155 - 2⁴ = 638085139 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115241 + ... + 120650.

It is an arithmetic number, because the mean of its divisors is an integer number (95890098).

Almost surely, 2^638085155 is an apocalyptic number.

638085155 is a deficient number, since it is larger than the sum of its proper divisors (129035629).

638085155 is a wasteful number, since it uses less digits than its factorization.

638085155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236437.

The product of its (nonzero) digits is 144000, while the sum is 41.

The square root of 638085155 is about 25260.3474837541. The cubic root of 638085155 is about 860.9135573297.

The spelling of 638085155 in words is "six hundred thirty-eight million, eighty-five thousand, one hundred fifty-five".