201021011111001 has 4 divisors (see below), whose sum is σ = 268028014814672. Its totient is φ = 134014007407332.

The previous prime is 201021011110993. The next prime is 201021011111051. The reversal of 201021011111001 is 100111110120102.

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 not a de Polignac number, because 201021011111001 - 2³ = 201021011110993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201021011111051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33503501851831 + ... + 33503501851836.

It is an arithmetic number, because the mean of its divisors is an integer number (67007003703668).

Almost surely, 2^{201021011111001} is an apocalyptic number.

It is an amenable number.

201021011111001 is a deficient number, since it is larger than the sum of its proper divisors (67007003703671).

201021011111001 is an equidigital number, since it uses as much as digits as its factorization.

201021011111001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67007003703670.

The product of its (nonzero) digits is 4, while the sum is 12.

Adding to 201021011111001 its reverse (100111110120102), we get a palindrome (301132121231103).

The spelling of 201021011111001 in words is "two hundred one trillion, twenty-one billion, eleven million, one hundred eleven thousand, one".