21624107 has 2 divisors, whose sum is σ = 21624108. Its totient is φ = 21624106.

The previous prime is 21624101. The next prime is 21624137. The reversal of 21624107 is 70142612.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21624107 is a prime.

It is not a weakly prime, because it can be changed into another prime (21624101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10812053 + 10812054.

It is an arithmetic number, because the mean of its divisors is an integer number (10812054).

Almost surely, 2^21624107 is an apocalyptic number.

21624107 is a deficient number, since it is larger than the sum of its proper divisors (1).

21624107 is an equidigital number, since it uses as much as digits as its factorization.

21624107 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 21624107 is about 4650.1727924885. The cubic root of 21624107 is about 278.5988977765.

Adding to 21624107 its reverse (70142612), we get a palindrome (91766719).

The spelling of 21624107 in words is "twenty-one million, six hundred twenty-four thousand, one hundred seven".