201681305 has 24 divisors (see below), whose sum is σ = 282818952. Its totient is φ = 137663232.

The previous prime is 201681301. The next prime is 201681307. The reversal of 201681305 is 503186102.

It can be written as a sum of positive squares in 4 ways, for example, as 21799561 + 179881744 = 4669^2 + 13412^2 .

It is not a de Polignac number, because 201681305 - 2² = 201681301 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (201681301) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55319 + ... + 58851.

It is an arithmetic number, because the mean of its divisors is an integer number (11784123).

Almost surely, 2^201681305 is an apocalyptic number.

It is an amenable number.

201681305 is a deficient number, since it is larger than the sum of its proper divisors (81137647).

201681305 is a wasteful number, since it uses less digits than its factorization.

201681305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3785 (or 3778 counting only the distinct ones).

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

The square root of 201681305 is about 14201.4543269343. The cubic root of 201681305 is about 586.4376988647.

The spelling of 201681305 in words is "two hundred one million, six hundred eighty-one thousand, three hundred five".