20668736694 has 8 divisors (see below), whose sum is σ = 41337473400. Its totient is φ = 6889578896.

The previous prime is 20668736677. The next prime is 20668736723. The reversal of 20668736694 is 49663786602.

It is a happy number.

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

20668736694 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1722394719 + ... + 1722394730.

It is an arithmetic number, because the mean of its divisors is an integer number (5167184175).

Almost surely, 2^20668736694 is an apocalyptic number.

20668736694 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20668736694 is a wasteful number, since it uses less digits than its factorization.

20668736694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3444789454.

The product of its (nonzero) digits is 15676416, while the sum is 57.

The spelling of 20668736694 in words is "twenty billion, six hundred sixty-eight million, seven hundred thirty-six thousand, six hundred ninety-four".