91831010210021 has 16 divisors (see below), whose sum is σ = 95905936960128. Its totient is φ = 87762946814400.

The previous prime is 91831010210011. The next prime is 91831010210059. The reversal of 91831010210021 is 12001201013819.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91831010210021 is a prime.

It is a super-2 number, since 2×91831010210021² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91831010210011) 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, 662582951 + ... + 662721531.

It is an arithmetic number, because the mean of its divisors is an integer number (5994121060008).

Almost surely, 2^{91831010210021} is an apocalyptic number.

It is an amenable number.

91831010210021 is a deficient number, since it is larger than the sum of its proper divisors (4074926750107).

91831010210021 is a wasteful number, since it uses less digits than its factorization.

91831010210021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163132.

The product of its (nonzero) digits is 864, while the sum is 29.

The spelling of 91831010210021 in words is "ninety-one trillion, eight hundred thirty-one billion, ten million, two hundred ten thousand, twenty-one".