123865789 has 4 divisors (see below), whose sum is σ = 123889024. Its totient is φ = 123842556.

The previous prime is 123865783. The next prime is 123865793. The reversal of 123865789 is 987568321.

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: 987568321 = 1823 ⋅541727.

It is a cyclic number.

It is not a de Polignac number, because 123865789 - 2²⁵ = 90311357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123865783) 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, 814 + ... + 15760.

It is an arithmetic number, because the mean of its divisors is an integer number (30972256).

Almost surely, 2^123865789 is an apocalyptic number.

It is an amenable number.

123865789 is a deficient number, since it is larger than the sum of its proper divisors (23235).

123865789 is an equidigital number, since it uses as much as digits as its factorization.

123865789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23234.

The product of its digits is 725760, while the sum is 49.

The square root of 123865789 is about 11129.5008423559. The cubic root of 123865789 is about 498.4831214794.

The spelling of 123865789 in words is "one hundred twenty-three million, eight hundred sixty-five thousand, seven hundred eighty-nine".