639155 has 8 divisors (see below), whose sum is σ = 836784. Its totient is φ = 464800.

The previous prime is 639151. The next prime is 639157. The reversal of 639155 is 551936.

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

It is not a de Polignac number, because 639155 - 2² = 639151 is a prime.

It is a super-2 number, since 2×639155² = 817038228050, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (639151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5756 + ... + 5865.

It is an arithmetic number, because the mean of its divisors is an integer number (104598).

2⁶³⁹¹⁵⁵ is an apocalyptic number.

639155 is a deficient number, since it is larger than the sum of its proper divisors (197629).

639155 is a wasteful number, since it uses less digits than its factorization.

639155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11637.

The product of its digits is 4050, while the sum is 29.

The square root of 639155 is about 799.4717005623. The cubic root of 639155 is about 86.1394438698.

It can be divided in two parts, 6391 and 55, that added together give a palindrome (6446).

The spelling of 639155 in words is "six hundred thirty-nine thousand, one hundred fifty-five".