21201599 has 2 divisors, whose sum is σ = 21201600. Its totient is φ = 21201598.

The previous prime is 21201577. The next prime is 21201611. The reversal of 21201599 is 99510212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21201599 - 2²⁴ = 4424383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21201539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600799 + 10600800.

It is an arithmetic number, because the mean of its divisors is an integer number (10600800).

Almost surely, 2^21201599 is an apocalyptic number.

21201599 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201599 is an equidigital number, since it uses as much as digits as its factorization.

21201599 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 21201599 is about 4604.5194103185. The cubic root of 21201599 is about 276.7724588564.

The spelling of 21201599 in words is "twenty-one million, two hundred one thousand, five hundred ninety-nine".