201091001 has 4 divisors (see below), whose sum is σ = 209834112. Its totient is φ = 192347892.

The previous prime is 201090979. The next prime is 201091013. The reversal of 201091001 is 100190102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201091001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201091031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4371521 + ... + 4371566.

It is an arithmetic number, because the mean of its divisors is an integer number (52458528).

Almost surely, 2^201091001 is an apocalyptic number.

It is an amenable number.

201091001 is a deficient number, since it is larger than the sum of its proper divisors (8743111).

201091001 is an equidigital number, since it uses as much as digits as its factorization.

201091001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8743110.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 201091001 is about 14180.6558734073. The cubic root of 201091001 is about 585.8649886793.

The spelling of 201091001 in words is "two hundred one million, ninety-one thousand, one".