20866673969 has 4 divisors (see below), whose sum is σ = 20868520740. Its totient is φ = 20864827200.

The previous prime is 20866673951. The next prime is 20866673983. The reversal of 20866673969 is 96937666802.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11206339600 + 9660334369 = 105860^2 + 98287^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20866673969 is a prime.

It is a super-2 number, since 2×20866673969² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20866673999) 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, 906332 + ... + 929069.

It is an arithmetic number, because the mean of its divisors is an integer number (5217130185).

Almost surely, 2^20866673969 is an apocalyptic number.

It is an amenable number.

20866673969 is a deficient number, since it is larger than the sum of its proper divisors (1846771).

20866673969 is a wasteful number, since it uses less digits than its factorization.

20866673969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1846770.

The product of its (nonzero) digits is 35271936, while the sum is 62.

The spelling of 20866673969 in words is "twenty billion, eight hundred sixty-six million, six hundred seventy-three thousand, nine hundred sixty-nine".