20001245544 has 128 divisors (see below), whose sum is σ = 64209888000. Its totient is φ = 5650394112.

The previous prime is 20001245543. The next prime is 20001245573. The reversal of 20001245544 is 44554210002.

20001245544 is a `hidden beast` number, since 200 + 0 + 1 + 2 + 455 + 4 + 4 = 666.

It is a super-2 number, since 2×20001245544² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20001245543) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 60252 + ... + 208884.

It is an arithmetic number, because the mean of its divisors is an integer number (501639750).

Almost surely, 2^20001245544 is an apocalyptic number.

20001245544 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20001245544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32104944000).

20001245544 is an abundant number, since it is smaller than the sum of its proper divisors (44208642456).

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

20001245544 is a wasteful number, since it uses less digits than its factorization.

20001245544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148744 (or 148734 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 27.

Adding to 20001245544 its reverse (44554210002), we get a palindrome (64555455546).

The spelling of 20001245544 in words is "twenty billion, one million, two hundred forty-five thousand, five hundred forty-four".