20444563540 has 36 divisors (see below), whose sum is σ = 45312191316. Its totient is φ = 7747410816.

The previous prime is 20444563507. The next prime is 20444563547. The reversal of 20444563540 is 4536544402.

It can be written as a sum of positive squares in 2 ways, for example, as 8359079184 + 12085484356 = 91428^2 + 109934^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20444563540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20444563547) 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, 1408609 + ... + 1423048.

It is an arithmetic number, because the mean of its divisors is an integer number (1258671981).

Almost surely, 2^20444563540 is an apocalyptic number.

20444563540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20444563540 is an abundant number, since it is smaller than the sum of its proper divisors (24867627776).

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

20444563540 is a wasteful number, since it uses less digits than its factorization.

20444563540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2831704 (or 2831683 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 37.

The spelling of 20444563540 in words is "twenty billion, four hundred forty-four million, five hundred sixty-three thousand, five hundred forty".