720128123 has 8 divisors (see below), whose sum is σ = 846024816. Its totient is φ = 604303200.

The previous prime is 720128039. The next prime is 720128131. The reversal of 720128123 is 321821027.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 720128123 - 2¹⁰ = 720127099 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 720128092 and 720128101.

It is not an unprimeable number, because it can be changed into a prime (720128153) 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, 2517788 + ... + 2518073.

It is an arithmetic number, because the mean of its divisors is an integer number (105753102).

Almost surely, 2^720128123 is an apocalyptic number.

720128123 is a deficient number, since it is larger than the sum of its proper divisors (125896693).

720128123 is a wasteful number, since it uses less digits than its factorization.

720128123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5035885.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 720128123 is about 26835.2030549426. The cubic root of 720128123 is about 896.3341101416.

The spelling of 720128123 in words is "seven hundred twenty million, one hundred twenty-eight thousand, one hundred twenty-three".