Search a number
23456789 is a prime number

23456789 has 2 divisors, whose sum is σ = 23456790. Its totient is φ = 23456788.

The previous prime is 23456761. The next prime is 23456819. The reversal of 23456789 is 98765432.

Adding to 23456789 its reverse (98765432), we get a palindrome (122222221).

23456789 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22486564 + 970225 = 4742^2 + 985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2k-23456789 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is a straight-line number, since its digits are in arithmetic progression.

It is a plaindrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23456749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11728394 + 11728395.

It is an arithmetic number, because the mean of its divisors is an integer number (11728395).

Almost surely, 223456789 is an apocalyptic number.

It is an amenable number.

23456789 is a deficient number, since it is larger than the sum of its proper divisors (1).

23456789 is an equidigital number, since it uses as much as digits as its factorization.

23456789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 362880, while the sum is 44.

The square root of 23456789 is about 4843.2209323961. The cubic root of 23456789 is about 286.2570471750.

The spelling of 23456789 in words is "twenty-three million, four hundred fifty-six thousand, seven hundred eighty-nine".