20679640207 has 4 divisors (see below), whose sum is σ = 20713375960. Its totient is φ = 20645904456.

The previous prime is 20679640151. The next prime is 20679640211. The reversal of 20679640207 is 70204697602.

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-20679640207 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 (20679640217) 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, 16866957 + ... + 16868182.

It is an arithmetic number, because the mean of its divisors is an integer number (5178343990).

Almost surely, 2^20679640207 is an apocalyptic number.

20679640207 is a deficient number, since it is larger than the sum of its proper divisors (33735753).

20679640207 is an equidigital number, since it uses as much as digits as its factorization.

20679640207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33735752.

The product of its (nonzero) digits is 254016, while the sum is 43.

The spelling of 20679640207 in words is "twenty billion, six hundred seventy-nine million, six hundred forty thousand, two hundred seven".