23081521 has 2 divisors, whose sum is σ = 23081522. Its totient is φ = 23081520.

The previous prime is 23081519. The next prime is 23081543. The reversal of 23081521 is 12518032.

It is an a-pointer prime, because the next prime (23081543) can be obtained adding 23081521 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14930496 + 8151025 = 3864^2 + 2855^2 .

It is a cyclic number.

It is not a de Polignac number, because 23081521 - 2¹ = 23081519 is a prime.

It is a super-2 number, since 2×23081521² = 1065513223346882, which contains 22 as substring.

Together with 23081519, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 23081492 and 23081501.

It is not a weakly prime, because it can be changed into another prime (23081551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11540760 + 11540761.

It is an arithmetic number, because the mean of its divisors is an integer number (11540761).

Almost surely, 2^23081521 is an apocalyptic number.

It is an amenable number.

23081521 is a deficient number, since it is larger than the sum of its proper divisors (1).

23081521 is an equidigital number, since it uses as much as digits as its factorization.

23081521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 23081521 is about 4804.3231573240. The cubic root of 23081521 is about 284.7222943817.

Adding to 23081521 its reverse (12518032), we get a palindrome (35599553).

The spelling of 23081521 in words is "twenty-three million, eighty-one thousand, five hundred twenty-one".