21502441 has 2 divisors, whose sum is σ = 21502442. Its totient is φ = 21502440.

The previous prime is 21502387. The next prime is 21502463. The reversal of 21502441 is 14420512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20894041 + 608400 = 4571^2 + 780^2 .

It is a cyclic number.

It is not a de Polignac number, because 21502441 - 2⁹ = 21501929 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21502241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10751220 + 10751221.

It is an arithmetic number, because the mean of its divisors is an integer number (10751221).

Almost surely, 2^21502441 is an apocalyptic number.

It is an amenable number.

21502441 is a deficient number, since it is larger than the sum of its proper divisors (1).

21502441 is an equidigital number, since it uses as much as digits as its factorization.

21502441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 21502441 is about 4637.0724600765. The cubic root of 21502441 is about 278.0754112828.

Adding to 21502441 its reverse (14420512), we get a palindrome (35922953).

The spelling of 21502441 in words is "twenty-one million, five hundred two thousand, four hundred forty-one".