123720 has 32 divisors (see below), whose sum is σ = 371520. Its totient is φ = 32960.

The previous prime is 123719. The next prime is 123727. The reversal of 123720 is 27321.

It is a hoax number, since the sum of its digits (15) coincides with the sum of the digits of its distinct prime factors.

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

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 123720.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 123720.

It is not an unprimeable number, because it can be changed into a prime (123727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 396 + ... + 635.

It is an arithmetic number, because the mean of its divisors is an integer number (11610).

2¹²³⁷²⁰ is an apocalyptic number.

123720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123720 is an abundant number, since it is smaller than the sum of its proper divisors (247800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

123720 is a wasteful number, since it uses less digits than its factorization.

123720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1045 (or 1041 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 15.

The square root of 123720 is about 351.7385392589. The cubic root of 123720 is about 49.8287474543.

The spelling of 123720 in words is "one hundred twenty-three thousand, seven hundred twenty", and thus it is an iban number.