23143509 has 8 divisors (see below), whose sum is σ = 34286720. Its totient is φ = 15428988.

The previous prime is 23143493. The next prime is 23143513. The reversal of 23143509 is 90534132.

It is not a de Polignac number, because 23143509 - 2⁴ = 23143493 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 857167 = 23143509 / (2 + 3 + 1 + 4 + 3 + 5 + 0 + 9).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23143529) 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, 428557 + ... + 428610.

It is an arithmetic number, because the mean of its divisors is an integer number (4285840).

Almost surely, 2^23143509 is an apocalyptic number.

It is an amenable number.

23143509 is a deficient number, since it is larger than the sum of its proper divisors (11143211).

23143509 is an equidigital number, since it uses as much as digits as its factorization.

23143509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 857176 (or 857170 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 23143509 is about 4810.7701046714. The cubic root of 23143509 is about 284.9769510446.

The spelling of 23143509 in words is "twenty-three million, one hundred forty-three thousand, five hundred nine".