21668124194 has 8 divisors (see below), whose sum is σ = 33294922668. Its totient is φ = 10569816640.

The previous prime is 21668124173. The next prime is 21668124199. The reversal of 21668124194 is 49142186612.

It can be written as a sum of positive squares in 2 ways, for example, as 20789890969 + 878233225 = 144187^2 + 29635^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21668124199) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 132122627 + ... + 132122790.

Almost surely, 2^21668124194 is an apocalyptic number.

21668124194 is a deficient number, since it is larger than the sum of its proper divisors (11626798474).

21668124194 is a wasteful number, since it uses less digits than its factorization.

21668124194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264245460.

The product of its digits is 165888, while the sum is 44.

The spelling of 21668124194 in words is "twenty-one billion, six hundred sixty-eight million, one hundred twenty-four thousand, one hundred ninety-four".