91428577720 has 32 divisors (see below), whose sum is σ = 205723469520. Its totient is φ = 36569800960.

The previous prime is 91428577687. The next prime is 91428577741. The reversal of 91428577720 is 2777582419.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1299855 + ... + 1368385.

Almost surely, 2^91428577720 is an apocalyptic number.

It is an amenable number.

91428577720 is an abundant number, since it is smaller than the sum of its proper divisors (114294891800).

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

91428577720 is a wasteful number, since it uses less digits than its factorization.

91428577720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101895 (or 101891 counting only the distinct ones).

The product of its (nonzero) digits is 1975680, while the sum is 52.

The spelling of 91428577720 in words is "ninety-one billion, four hundred twenty-eight million, five hundred seventy-seven thousand, seven hundred twenty".