20623436644 has 24 divisors (see below), whose sum is σ = 38218701528. Its totient is φ = 9703956480.

The previous prime is 20623436599. The next prime is 20623436671. The reversal of 20623436644 is 44663432602.

It can be written as a sum of positive squares in 4 ways, for example, as 779079744 + 19844356900 = 27912^2 + 140870^2 .

It is a super-3 number, since 3×20623436644³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 20623436597 and 20623436606.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 808404 + ... + 833524.

It is an arithmetic number, because the mean of its divisors is an integer number (1592445897).

Almost surely, 2^20623436644 is an apocalyptic number.

It is an amenable number.

20623436644 is a deficient number, since it is larger than the sum of its proper divisors (17595264884).

20623436644 is a wasteful number, since it uses less digits than its factorization.

20623436644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37215 (or 37213 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 40.

The spelling of 20623436644 in words is "twenty billion, six hundred twenty-three million, four hundred thirty-six thousand, six hundred forty-four".