139669 has 4 divisors (see below), whose sum is σ = 147040.
Its totient is φ = 132300.
The previous prime is 139663. The next prime is 139681. The reversal of 139669 is 966931.
It can be divided in two parts, 139 and 669, that added together give a palindrome (808).
It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.
It is a cyclic number.
It is not a de Polignac number, because 139669 - 23 = 139661 is a prime.
It is a super-2 number, since 2×1396692 = 39014859122, which contains 22 as substring.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (139661) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3657 + ... + 3694.
It is an arithmetic number, because the mean of its divisors is an integer number (36760).
2139669 is an apocalyptic number.
139669 is a gapful number since it is divisible by the number (19) formed by its first and last digit.
It is an amenable number.
139669 is a deficient number, since it is larger than the sum of its proper divisors (7371).
139669 is an equidigital number, since it uses as much as digits as its factorization.
139669 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 7370.
The product of its digits is 8748, while the sum is 34.
The square root of 139669 is about 373.7231595714.
The cubic root of 139669 is about 51.8839869271.
The spelling of 139669 in words is "one hundred thirty-nine thousand, six hundred sixty-nine".