20015344656 has 60 divisors (see below), whose sum is σ = 56087942508. Its totient is φ = 6663113472.

The previous prime is 20015344651. The next prime is 20015344663. The reversal of 20015344656 is 65644351002.

20015344656 is a `hidden beast` number, since 200 + 1 + 5 + 3 + 446 + 5 + 6 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 4093952256 + 15921392400 = 63984^2 + 126180^2 .

It is a super-2 number, since 2×20015344656² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 20015344656.

It is not an unprimeable number, because it can be changed into a prime (20015344651) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21406 + ... + 201218.

Almost surely, 2^20015344656 is an apocalyptic number.

It is an amenable number.

20015344656 is an abundant number, since it is smaller than the sum of its proper divisors (36072597852).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20015344656 is a wasteful number, since it uses less digits than its factorization.

20015344656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180600 (or 180591 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

Adding to 20015344656 its reverse (65644351002), we get a palindrome (85659695658).

The spelling of 20015344656 in words is "twenty billion, fifteen million, three hundred forty-four thousand, six hundred fifty-six".