91020022121 has 16 divisors (see below), whose sum is σ = 104228069376. Its totient is φ = 77863430736.

The previous prime is 91020022109. The next prime is 91020022151. The reversal of 91020022121 is 12122002019.

It is a happy number.

It is not a de Polignac number, because 91020022121 - 2²⁶ = 90952913257 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91020022093 and 91020022102.

It is not an unprimeable number, because it can be changed into a prime (91020022151) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8233820 + ... + 8244866.

It is an arithmetic number, because the mean of its divisors is an integer number (6514254336).

Almost surely, 2^91020022121 is an apocalyptic number.

It is an amenable number.

91020022121 is a deficient number, since it is larger than the sum of its proper divisors (13208047255).

91020022121 is a wasteful number, since it uses less digits than its factorization.

91020022121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13268.

The product of its (nonzero) digits is 144, while the sum is 20.

The spelling of 91020022121 in words is "ninety-one billion, twenty million, twenty-two thousand, one hundred twenty-one".