21231107 has 2 divisors, whose sum is σ = 21231108. Its totient is φ = 21231106.

The previous prime is 21231029. The next prime is 21231143. The reversal of 21231107 is 70113212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21231107 - 2⁸ = 21230851 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21231307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10615553 + 10615554.

It is an arithmetic number, because the mean of its divisors is an integer number (10615554).

Almost surely, 2^21231107 is an apocalyptic number.

21231107 is a deficient number, since it is larger than the sum of its proper divisors (1).

21231107 is an equidigital number, since it uses as much as digits as its factorization.

21231107 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 21231107 is about 4607.7225393897. The cubic root of 21231107 is about 276.9008016251.

Adding to 21231107 its reverse (70113212), we get a palindrome (91344319).

The spelling of 21231107 in words is "twenty-one million, two hundred thirty-one thousand, one hundred seven".