23516021 has 2 divisors, whose sum is σ = 23516022. Its totient is φ = 23516020.

The previous prime is 23515997. The next prime is 23516023. The reversal of 23516021 is 12061532.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22193521 + 1322500 = 4711^2 + 1150^2 .

It is a cyclic number.

It is not a de Polignac number, because 23516021 - 2⁶ = 23515957 is a prime.

Together with 23516023, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 23515984 and 23516002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23516023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11758010 + 11758011.

It is an arithmetic number, because the mean of its divisors is an integer number (11758011).

Almost surely, 2^23516021 is an apocalyptic number.

It is an amenable number.

23516021 is a deficient number, since it is larger than the sum of its proper divisors (1).

23516021 is an equidigital number, since it uses as much as digits as its factorization.

23516021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 23516021 is about 4849.3320158554. The cubic root of 23516021 is about 286.4977923396.

Adding to 23516021 its reverse (12061532), we get a palindrome (35577553).

The spelling of 23516021 in words is "twenty-three million, five hundred sixteen thousand, twenty-one".