21825151 has 2 divisors, whose sum is σ = 21825152. Its totient is φ = 21825150.

The previous prime is 21825149. The next prime is 21825163. The reversal of 21825151 is 15152812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21825151 - 2¹ = 21825149 is a prime.

Together with 21825149, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21825751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10912575 + 10912576.

It is an arithmetic number, because the mean of its divisors is an integer number (10912576).

Almost surely, 2^21825151 is an apocalyptic number.

21825151 is a deficient number, since it is larger than the sum of its proper divisors (1).

21825151 is an equidigital number, since it uses as much as digits as its factorization.

21825151 is an evil number, because the sum of its binary digits is even.

The product of its digits is 800, while the sum is 25.

The square root of 21825151 is about 4671.7396117506. The cubic root of 21825151 is about 279.4596338499.

Adding to 21825151 its reverse (15152812), we get a palindrome (36977963).

The spelling of 21825151 in words is "twenty-one million, eight hundred twenty-five thousand, one hundred fifty-one".