20945104679 has 4 divisors (see below), whose sum is σ = 20962840920. Its totient is φ = 20927368440.

The previous prime is 20945104667. The next prime is 20945104703. The reversal of 20945104679 is 97640154902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20945104679 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20945103679) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 8866349 + ... + 8868710.

It is an arithmetic number, because the mean of its divisors is an integer number (5240710230).

Almost surely, 2^20945104679 is an apocalyptic number.

20945104679 is a deficient number, since it is larger than the sum of its proper divisors (17736241).

20945104679 is a wasteful number, since it uses less digits than its factorization.

20945104679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17736240.

The product of its (nonzero) digits is 544320, while the sum is 47.

The spelling of 20945104679 in words is "twenty billion, nine hundred forty-five million, one hundred four thousand, six hundred seventy-nine".