9201020021 has 4 divisors (see below), whose sum is σ = 9236005152. Its totient is φ = 9166034892.

The previous prime is 9201019999. The next prime is 9201020039. The reversal of 9201020021 is 1200201029.

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-9201020021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9201025021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17492171 + ... + 17492696.

It is an arithmetic number, because the mean of its divisors is an integer number (2309001288).

Almost surely, 2^9201020021 is an apocalyptic number.

It is an amenable number.

9201020021 is a deficient number, since it is larger than the sum of its proper divisors (34985131).

9201020021 is a wasteful number, since it uses less digits than its factorization.

9201020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34985130.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 9201020021 is about 95921.9475459084. The cubic root of 9201020021 is about 2095.4565429993.

The spelling of 9201020021 in words is "nine billion, two hundred one million, twenty thousand, twenty-one".