21235099 has 2 divisors, whose sum is σ = 21235100. Its totient is φ = 21235098.

The previous prime is 21235079. The next prime is 21235111. The reversal of 21235099 is 99053212.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21235099 is a prime.

It is equal to p_1343839 and since 21235099 and 1343839 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21235099.

It is not a weakly prime, because it can be changed into another prime (21235009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10617549 + 10617550.

It is an arithmetic number, because the mean of its divisors is an integer number (10617550).

Almost surely, 2^21235099 is an apocalyptic number.

21235099 is a deficient number, since it is larger than the sum of its proper divisors (1).

21235099 is an equidigital number, since it uses as much as digits as its factorization.

21235099 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 21235099 is about 4608.1557048346. The cubic root of 21235099 is about 276.9181553870.

The spelling of 21235099 in words is "twenty-one million, two hundred thirty-five thousand, ninety-nine".