21622151 has 2 divisors, whose sum is σ = 21622152. Its totient is φ = 21622150.

The previous prime is 21622141. The next prime is 21622157. The reversal of 21622151 is 15122612.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21622151 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21622157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10811075 + 10811076.

It is an arithmetic number, because the mean of its divisors is an integer number (10811076).

Almost surely, 2^21622151 is an apocalyptic number.

21622151 is a deficient number, since it is larger than the sum of its proper divisors (1).

21622151 is an equidigital number, since it uses as much as digits as its factorization.

21622151 is an evil number, because the sum of its binary digits is even.

The product of its digits is 240, while the sum is 20.

The square root of 21622151 is about 4649.9624729669. The cubic root of 21622151 is about 278.5904973391.

Adding to 21622151 its reverse (15122612), we get a palindrome (36744763).

The spelling of 21622151 in words is "twenty-one million, six hundred twenty-two thousand, one hundred fifty-one".