201231433728 has 418 divisors, whose sum is σ = 650127414314. Its totient is φ = 61917364224.

The previous prime is 201231433721. The next prime is 201231433747. The reversal of 201231433728 is 827334132102.

201231433728 is a `hidden beast` number, since 2 + 0 + 1 + 2 + 314 + 337 + 2 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 139314069504 + 61917364224 = 373248^2 + 248832^2 .

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

It is a nialpdrome in base 12.

It is a zygodrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 201231433692 and 201231433701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201231433721) by changing a digit.

It is a polite number, since it can be written in 21 ways as a sum of consecutive naturals, for example, 15479341050 + ... + 15479341062.

Almost surely, 2^201231433728 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 201231433728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (325063707157).

201231433728 is an abundant number, since it is smaller than the sum of its proper divisors (448895980586).

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

201231433728 is an frugal number, since it uses more digits than its factorization.

201231433728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79 (or 18 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The spelling of 201231433728 in words is "two hundred one billion, two hundred thirty-one million, four hundred thirty-three thousand, seven hundred twenty-eight".