20011640544 has 384 divisors, whose sum is σ = 69998100480. Its totient is φ = 5438264832.

The previous prime is 20011640507. The next prime is 20011640569. The reversal of 20011640544 is 44504611002.

20011640544 is a `hidden beast` number, since 2 + 0 + 0 + 11 + 640 + 5 + 4 + 4 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 36584079 + ... + 36584625.

It is an arithmetic number, because the mean of its divisors is an integer number (182286720).

Almost surely, 2^20011640544 is an apocalyptic number.

20011640544 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 20011640544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34999050240).

20011640544 is an abundant number, since it is smaller than the sum of its proper divisors (49986459936).

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

20011640544 is a wasteful number, since it uses less digits than its factorization.

20011640544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 859 (or 845 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The spelling of 20011640544 in words is "twenty billion, eleven million, six hundred forty thousand, five hundred forty-four".