20766640207 has 4 divisors (see below), whose sum is σ = 21988207296. Its totient is φ = 19545073120.

The previous prime is 20766640157. The next prime is 20766640211. The reversal of 20766640207 is 70204666702.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 20766640207 - 2¹⁵ = 20766607439 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20766640207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20766640267) 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, 610783519 + ... + 610783552.

It is an arithmetic number, because the mean of its divisors is an integer number (5497051824).

Almost surely, 2^20766640207 is an apocalyptic number.

20766640207 is a deficient number, since it is larger than the sum of its proper divisors (1221567089).

20766640207 is a wasteful number, since it uses less digits than its factorization.

20766640207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1221567088.

The product of its (nonzero) digits is 169344, while the sum is 40.

The spelling of 20766640207 in words is "twenty billion, seven hundred sixty-six million, six hundred forty thousand, two hundred seven".