91871802228 has 24 divisors (see below), whose sum is σ = 225650041120. Its totient is φ = 29012148000.

The previous prime is 91871802221. The next prime is 91871802229. The reversal of 91871802228 is 82220817819.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91871802221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 201473023 + ... + 201473478.

Almost surely, 2^91871802228 is an apocalyptic number.

It is an amenable number.

91871802228 is an abundant number, since it is smaller than the sum of its proper divisors (133778238892).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91871802228 is a wasteful number, since it uses less digits than its factorization.

91871802228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402946527 (or 402946525 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 48.

The spelling of 91871802228 in words is "ninety-one billion, eight hundred seventy-one million, eight hundred two thousand, two hundred twenty-eight".