19421690166 has 64 divisors (see below), whose sum is σ = 44833694400. Its totient is φ = 6224601600.

The previous prime is 19421690149. The next prime is 19421690213. The reversal of 19421690166 is 66109612491.

It is a happy number.

19421690166 is a `hidden beast` number, since 1 + 9 + 421 + 69 + 0 + 166 = 666.

It is a super-2 number, since 2×19421690166² (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 31 ways as a sum of consecutive naturals, for example, 351676 + ... + 403136.

It is an arithmetic number, because the mean of its divisors is an integer number (700526475).

Almost surely, 2^19421690166 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19421690166, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22416847200).

19421690166 is an abundant number, since it is smaller than the sum of its proper divisors (25412004234).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19421690166 is a wasteful number, since it uses less digits than its factorization.

19421690166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51742 (or 51736 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The spelling of 19421690166 in words is "nineteen billion, four hundred twenty-one million, six hundred ninety thousand, one hundred sixty-six".