139408 has 10 divisors (see below), whose sum is σ = 270134. Its totient is φ = 69696.

The previous prime is 139397. The next prime is 139409. The reversal of 139408 is 804931.

It can be written as a sum of positive squares in only one way, i.e., 138384 + 1024 = 372^2 + 32^2 .

It is not an unprimeable number, because it can be changed into a prime (139409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4341 + ... + 4372.

2¹³⁹⁴⁰⁸ is an apocalyptic number.

It is an amenable number.

139408 is a deficient number, since it is larger than the sum of its proper divisors (130726).

139408 is an equidigital number, since it uses as much as digits as its factorization.

139408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8721 (or 8715 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 139408 is about 373.3738073299. The cubic root of 139408 is about 51.8516481725.

The spelling of 139408 in words is "one hundred thirty-nine thousand, four hundred eight".