20644778246 has 8 divisors (see below), whose sum is σ = 31687334184. Its totient is φ = 10082333520.

The previous prime is 20644778239. The next prime is 20644778249. The reversal of 20644778246 is 64287744602.

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

It is a junction number, because it is equal to n+sod(n) for n = 20644778194 and 20644778203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20644778249) 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, 120027695 + ... + 120027866.

It is an arithmetic number, because the mean of its divisors is an integer number (3960916773).

Almost surely, 2^20644778246 is an apocalyptic number.

20644778246 is a deficient number, since it is larger than the sum of its proper divisors (11042555938).

20644778246 is a wasteful number, since it uses less digits than its factorization.

20644778246 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240055606.

The product of its (nonzero) digits is 3612672, while the sum is 50.

The spelling of 20644778246 in words is "twenty billion, six hundred forty-four million, seven hundred seventy-eight thousand, two hundred forty-six".