21659413858 has 16 divisors (see below), whose sum is σ = 34541349696. Its totient is φ = 10163398960.

The previous prime is 21659413843. The next prime is 21659413859. The reversal of 21659413858 is 85831495612.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21659413859) 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 in 7 ways as a sum of consecutive naturals, for example, 4439608 + ... + 4444483.

It is an arithmetic number, because the mean of its divisors is an integer number (2158834356).

Almost surely, 2^21659413858 is an apocalyptic number.

21659413858 is a deficient number, since it is larger than the sum of its proper divisors (12881935838).

21659413858 is a wasteful number, since it uses less digits than its factorization.

21659413858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8884169.

The product of its digits is 2073600, while the sum is 52.

The spelling of 21659413858 in words is "twenty-one billion, six hundred fifty-nine million, four hundred thirteen thousand, eight hundred fifty-eight".