21166311670 has 32 divisors (see below), whose sum is σ = 43600214016. Its totient is φ = 7247340000.

The previous prime is 21166311659. The next prime is 21166311707. The reversal of 21166311670 is 7611366112.

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, 148746 + ... + 253885.

It is an arithmetic number, because the mean of its divisors is an integer number (1362506688).

Almost surely, 2^21166311670 is an apocalyptic number.

21166311670 is an abundant number, since it is smaller than the sum of its proper divisors (22433902346).

21166311670 is a wasteful number, since it uses less digits than its factorization.

21166311670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 403396.

The product of its (nonzero) digits is 9072, while the sum is 34.

Adding to 21166311670 its reverse (7611366112), we get a palindrome (28777677782).

The spelling of 21166311670 in words is "twenty-one billion, one hundred sixty-six million, three hundred eleven thousand, six hundred seventy".