20013515636400 has 720 divisors, whose sum is σ = 81621015420672. Its totient is φ = 4477093632000.

The previous prime is 20013515636293. The next prime is 20013515636417. The reversal of 20013515636400 is 463651531002.

20013515636400 is a `hidden beast` number, since 2 + 0 + 0 + 1 + 3 + 5 + 1 + 5 + 6 + 3 + 640 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

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

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 2729980735 + ... + 2729988065.

Almost surely, 2^{20013515636400} is an apocalyptic number.

20013515636400 is a gapful number since it is divisible by the number (20) 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 20013515636400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40810507710336).

20013515636400 is an abundant number, since it is smaller than the sum of its proper divisors (61607499784272).

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

20013515636400 is a wasteful number, since it uses less digits than its factorization.

20013515636400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12682 (or 12668 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The spelling of 20013515636400 in words is "twenty trillion, thirteen billion, five hundred fifteen million, six hundred thirty-six thousand, four hundred".