123749 has 4 divisors (see below), whose sum is σ = 125664. Its totient is φ = 121836.

The previous prime is 123737. The next prime is 123757. The reversal of 123749 is 947321.

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 123749 - 2⁴ = 123733 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a nialpdrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123719) 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, 857 + ... + 990.

It is an arithmetic number, because the mean of its divisors is an integer number (31416).

2¹²³⁷⁴⁹ is an apocalyptic number.

It is an amenable number.

123749 is a deficient number, since it is larger than the sum of its proper divisors (1915).

123749 is an equidigital number, since it uses as much as digits as its factorization.

123749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1914.

The product of its digits is 1512, while the sum is 26.

The square root of 123749 is about 351.7797606458. The cubic root of 123749 is about 49.8326404406.

The spelling of 123749 in words is "one hundred twenty-three thousand, seven hundred forty-nine".