20499659 has 2 divisors, whose sum is σ = 20499660. Its totient is φ = 20499658.

The previous prime is 20499571. The next prime is 20499673. The reversal of 20499659 is 95699402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20499659 - 2²⁴ = 3722443 is a prime.

It is a super-5 number, since 5×20499659⁵ (a number of 38 digits) contains 55555 as substring.

It is not a weakly prime, because it can be changed into another prime (20499679) 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, 10249829 + 10249830.

It is an arithmetic number, because the mean of its divisors is an integer number (10249830).

Almost surely, 2^20499659 is an apocalyptic number.

20499659 is a deficient number, since it is larger than the sum of its proper divisors (1).

20499659 is an equidigital number, since it uses as much as digits as its factorization.

20499659 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 174960, while the sum is 44.

The square root of 20499659 is about 4527.6549117617. The cubic root of 20499659 is about 273.6836662250.

The spelling of 20499659 in words is "twenty million, four hundred ninety-nine thousand, six hundred fifty-nine".