21003267166 has 32 divisors (see below), whose sum is σ = 37945474560. Its totient is φ = 8517553056.

The previous prime is 21003267149. The next prime is 21003267193. The reversal of 21003267166 is 66176230012.

It is a happy number.

It is a super-2 number, since 2×21003267166² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 180615 + ... + 273181.

It is an arithmetic number, because the mean of its divisors is an integer number (1185796080).

Almost surely, 2^21003267166 is an apocalyptic number.

21003267166 is a deficient number, since it is larger than the sum of its proper divisors (16942207394).

21003267166 is a wasteful number, since it uses less digits than its factorization.

21003267166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93448.

The product of its (nonzero) digits is 18144, while the sum is 34.

Adding to 21003267166 its reverse (66176230012), we get a palindrome (87179497178).

The spelling of 21003267166 in words is "twenty-one billion, three million, two hundred sixty-seven thousand, one hundred sixty-six".