201521972899728 has 640 divisors, whose sum is σ = 676964431503360. Its totient is φ = 56829516226560.

The previous prime is 201521972899657. The next prime is 201521972899747. The reversal of 201521972899728 is 827998279125102.

201521972899728 is a `hidden beast` number, since 2 + 0 + 1 + 52 + 197 + 289 + 97 + 28 = 666.

201521972899728 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×201521972899728² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1358778825 + ... + 1358927127.

It is an arithmetic number, because the mean of its divisors is an integer number (1057756924224).

Almost surely, 2^{201521972899728} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 201521972899728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (338482215751680).

201521972899728 is an abundant number, since it is smaller than the sum of its proper divisors (475442458603632).

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

201521972899728 is a wasteful number, since it uses less digits than its factorization.

201521972899728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148724 (or 148712 counting only the distinct ones).

The product of its (nonzero) digits is 182891520, while the sum is 72.

The spelling of 201521972899728 in words is "two hundred one trillion, five hundred twenty-one billion, nine hundred seventy-two million, eight hundred ninety-nine thousand, seven hundred twenty-eight".