139904 has 16 divisors (see below), whose sum is σ = 278970. Its totient is φ = 69888.

The previous prime is 139901. The next prime is 139907. The reversal of 139904 is 409931.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (139901) and next prime (139907).

It can be written as a sum of positive squares in only one way, i.e., 78400 + 61504 = 280^2 + 248^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 139904.

It is not an unprimeable number, because it can be changed into a prime (139901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 419 + ... + 674.

2¹³⁹⁹⁰⁴ is an apocalyptic number.

It is an amenable number.

139904 is a deficient number, since it is larger than the sum of its proper divisors (139066).

139904 is an equidigital number, since it uses as much as digits as its factorization.

139904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1107 (or 1095 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 139904 is about 374.0374312820. The cubic root of 139904 is about 51.9130697467.

The spelling of 139904 in words is "one hundred thirty-nine thousand, nine hundred four".