123671789 has 4 divisors (see below), whose sum is σ = 123782460. Its totient is φ = 123561120.

The previous prime is 123671783. The next prime is 123671809. The reversal of 123671789 is 987176321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 987176321 = 257 ⋅3841153.

It can be written as a sum of positive squares in 2 ways, for example, as 12369289 + 111302500 = 3517^2 + 10550^2 .

It is a cyclic number.

It is not a de Polignac number, because 123671789 - 2¹² = 123667693 is a prime.

It is a super-2 number, since 2×123671789² = 30589422788921042, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123671783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53642 + ... + 55899.

It is an arithmetic number, because the mean of its divisors is an integer number (30945615).

Almost surely, 2^123671789 is an apocalyptic number.

It is an amenable number.

123671789 is a deficient number, since it is larger than the sum of its proper divisors (110671).

123671789 is a wasteful number, since it uses less digits than its factorization.

123671789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110670.

The product of its digits is 127008, while the sum is 44.

The square root of 123671789 is about 11120.7818520102. The cubic root of 123671789 is about 498.2227421944. Note that the first 3 decimals are identical.

The spelling of 123671789 in words is "one hundred twenty-three million, six hundred seventy-one thousand, seven hundred eighty-nine".