123045 has 16 divisors (see below), whose sum is σ = 212352. Its totient is φ = 60480.

The previous prime is 123031. The next prime is 123049. The reversal of 123045 is 540321.

123045 = T₈₄ + T₈₅ + ... + T₁₀₉.

It is not a de Polignac number, because 123045 - 2⁸ = 122789 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

123045 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123049) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 121 + ... + 510.

It is an arithmetic number, because the mean of its divisors is an integer number (13272).

2¹²³⁰⁴⁵ is an apocalyptic number.

123045 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

123045 is a deficient number, since it is larger than the sum of its proper divisors (89307).

123045 is a wasteful number, since it uses less digits than its factorization.

123045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 652.

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 123045 is about 350.7777073875. Note that the first 4 decimals coincide. The cubic root of 123045 is about 49.7379624589.

Adding to 123045 its reverse (540321), we get a palindrome (663366).

It can be divided in two parts, 1230 and 45, that added together give a triangular number (1275 = T₅₀).

The spelling of 123045 in words is "one hundred twenty-three thousand, forty-five".