9811225021 has 4 divisors (see below), whose sum is σ = 10565934652. Its totient is φ = 9056515392.

The previous prime is 9811225001. The next prime is 9811225033. The reversal of 9811225021 is 1205221189.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2605592025 + 7205632996 = 51045^2 + 84886^2 .

It is a cyclic number.

It is not a de Polignac number, because 9811225021 - 2¹³ = 9811216829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9811225001) 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, 377354796 + ... + 377354821.

It is an arithmetic number, because the mean of its divisors is an integer number (2641483663).

Almost surely, 2^9811225021 is an apocalyptic number.

It is an amenable number.

9811225021 is a deficient number, since it is larger than the sum of its proper divisors (754709631).

9811225021 is a wasteful number, since it uses less digits than its factorization.

9811225021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 754709630.

The product of its (nonzero) digits is 2880, while the sum is 31.

The square root of 9811225021 is about 99051.6280583010. The cubic root of 9811225021 is about 2140.7916991679.

The spelling of 9811225021 in words is "nine billion, eight hundred eleven million, two hundred twenty-five thousand, twenty-one".