201187861 has 16 divisors (see below), whose sum is σ = 243145728. Its totient is φ = 162806400.

The previous prime is 201187837. The next prime is 201187873. The reversal of 201187861 is 168781102.

It is a cyclic number.

It is not a de Polignac number, because 201187861 - 2⁵ = 201187829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201187361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2410 + ... + 20203.

It is an arithmetic number, because the mean of its divisors is an integer number (15196608).

Almost surely, 2^201187861 is an apocalyptic number.

It is an amenable number.

201187861 is a deficient number, since it is larger than the sum of its proper divisors (41957867).

201187861 is a wasteful number, since it uses less digits than its factorization.

201187861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22692.

The product of its (nonzero) digits is 5376, while the sum is 34.

The square root of 201187861 is about 14184.0706780529. The cubic root of 201187861 is about 585.9590385934.

The spelling of 201187861 in words is "two hundred one million, one hundred eighty-seven thousand, eight hundred sixty-one".