201023021 has 4 divisors (see below), whose sum is σ = 211603200. Its totient is φ = 190442844.

The previous prime is 201022993. The next prime is 201023029. The reversal of 201023021 is 120320102.

It is a happy number.

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-201023021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201022993 and 201023011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201023029) 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, 5290061 + ... + 5290098.

It is an arithmetic number, because the mean of its divisors is an integer number (52900800).

Almost surely, 2^201023021 is an apocalyptic number.

It is an amenable number.

201023021 is a deficient number, since it is larger than the sum of its proper divisors (10580179).

201023021 is a wasteful number, since it uses less digits than its factorization.

201023021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10580178.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 201023021 is about 14178.2587435834. The cubic root of 201023021 is about 585.7989628659.

Adding to 201023021 its reverse (120320102), we get a palindrome (321343123).

The spelling of 201023021 in words is "two hundred one million, twenty-three thousand, twenty-one".