20646447386 has 8 divisors (see below), whose sum is σ = 30973001940. Its totient is φ = 10322113408.

The previous prime is 20646447379. The next prime is 20646447397. The reversal of 20646447386 is 68374464602.

It can be written as a sum of positive squares in 2 ways, for example, as 16481681161 + 4164766225 = 128381^2 + 64535^2 .

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

It is an unprimeable number.

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, 531701 + ... + 569208.

Almost surely, 2^20646447386 is an apocalyptic number.

20646447386 is a deficient number, since it is larger than the sum of its proper divisors (10326554554).

20646447386 is a wasteful number, since it uses less digits than its factorization.

20646447386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1110288.

The product of its (nonzero) digits is 4644864, while the sum is 50.

The spelling of 20646447386 in words is "twenty billion, six hundred forty-six million, four hundred forty-seven thousand, three hundred eighty-six".