9899122121 has 4 divisors (see below), whose sum is σ = 11313282432. Its totient is φ = 8484961812.

The previous prime is 9899122111. The next prime is 9899122127. The reversal of 9899122121 is 1212219989.

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 not a de Polignac number, because 9899122121 - 2²² = 9894927817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9899122127) 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, 707080145 + ... + 707080158.

It is an arithmetic number, because the mean of its divisors is an integer number (2828320608).

Almost surely, 2^9899122121 is an apocalyptic number.

It is an amenable number.

9899122121 is a deficient number, since it is larger than the sum of its proper divisors (1414160311).

9899122121 is a wasteful number, since it uses less digits than its factorization.

9899122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1414160310.

The product of its digits is 46656, while the sum is 44.

The square root of 9899122121 is about 99494.3321048993. The cubic root of 9899122121 is about 2147.1656988804.

The spelling of 9899122121 in words is "nine billion, eight hundred ninety-nine million, one hundred twenty-two thousand, one hundred twenty-one".