123949 has 4 divisors (see below), whose sum is σ = 141664. Its totient is φ = 106236.

The previous prime is 123941. The next prime is 123953. The reversal of 123949 is 949321.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 949321 = 641 ⋅1481.

It is a cyclic number.

It is not a de Polignac number, because 123949 - 2³ = 123941 is a prime.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123941) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8847 + ... + 8860.

It is an arithmetic number, because the mean of its divisors is an integer number (35416).

2¹²³⁹⁴⁹ is an apocalyptic number.

It is an amenable number.

123949 is a deficient number, since it is larger than the sum of its proper divisors (17715).

123949 is an equidigital number, since it uses as much as digits as its factorization.

123949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17714.

The product of its digits is 1944, while the sum is 28.

The square root of 123949 is about 352.0639146519. The cubic root of 123949 is about 49.8594720747.

It can be divided in two parts, 12394 and 9, that added together give a triangular number (12403 = T₁₅₇).

The spelling of 123949 in words is "one hundred twenty-three thousand, nine hundred forty-nine".