201591440 has 40 divisors (see below), whose sum is σ = 496274040. Its totient is φ = 75892736.

The previous prime is 201591433. The next prime is 201591451. The reversal of 201591440 is 44195102.

It can be written as a sum of positive squares in 4 ways, for example, as 115175824 + 86415616 = 10732^2 + 9296^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-3 number, since 3×201591440³ (a number of 26 digits) contains 333 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72755 + ... + 75474.

It is an arithmetic number, because the mean of its divisors is an integer number (12406851).

Almost surely, 2^201591440 is an apocalyptic number.

201591440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201591440 is an abundant number, since it is smaller than the sum of its proper divisors (294682600).

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

201591440 is a wasteful number, since it uses less digits than its factorization.

201591440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148259 (or 148253 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 201591440 is about 14198.2900378884. The cubic root of 201591440 is about 586.3505844391.

The spelling of 201591440 in words is "two hundred one million, five hundred ninety-one thousand, four hundred forty".