20901599 has 2 divisors, whose sum is σ = 20901600. Its totient is φ = 20901598.

The previous prime is 20901581. The next prime is 20901607. The reversal of 20901599 is 99510902.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20901599 - 2¹⁶ = 20836063 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20901509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10450799 + 10450800.

It is an arithmetic number, because the mean of its divisors is an integer number (10450800).

Almost surely, 2^20901599 is an apocalyptic number.

20901599 is a deficient number, since it is larger than the sum of its proper divisors (1).

20901599 is an equidigital number, since it uses as much as digits as its factorization.

20901599 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7290, while the sum is 35.

The square root of 20901599 is about 4571.8266590062. The cubic root of 20901599 is about 275.4608207543.

The spelling of 20901599 in words is "twenty million, nine hundred one thousand, five hundred ninety-nine".