21432107 has 2 divisors, whose sum is σ = 21432108. Its totient is φ = 21432106.

The previous prime is 21432097. The next prime is 21432157. The reversal of 21432107 is 70123412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21432107 - 2⁴ = 21432091 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (21432157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10716053 + 10716054.

It is an arithmetic number, because the mean of its divisors is an integer number (10716054).

Almost surely, 2^21432107 is an apocalyptic number.

21432107 is a deficient number, since it is larger than the sum of its proper divisors (1).

21432107 is an equidigital number, since it uses as much as digits as its factorization.

21432107 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21432107 is about 4629.4823684727. The cubic root of 21432107 is about 277.7718873003.

Adding to 21432107 its reverse (70123412), we get a palindrome (91555519).

The spelling of 21432107 in words is "twenty-one million, four hundred thirty-two thousand, one hundred seven".