91428868 has 12 divisors (see below), whose sum is σ = 161169372. Its totient is φ = 45380480.

The previous prime is 91428863. The next prime is 91428881. The reversal of 91428868 is 86882419.

It can be written as a sum of positive squares in 2 ways, for example, as 61748164 + 29680704 = 7858^2 + 5448^2 .

It is a super-2 number, since 2×91428868² = 16718475807522848, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91428863) 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, 82873 + ... + 83968.

It is an arithmetic number, because the mean of its divisors is an integer number (13430781).

Almost surely, 2^91428868 is an apocalyptic number.

It is an amenable number.

91428868 is a deficient number, since it is larger than the sum of its proper divisors (69740504).

91428868 is a wasteful number, since it uses less digits than its factorization.

91428868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166982 (or 166980 counting only the distinct ones).

The product of its digits is 221184, while the sum is 46.

The square root of 91428868 is about 9561.8443827538. The cubic root of 91428868 is about 450.4996392791.

The spelling of 91428868 in words is "ninety-one million, four hundred twenty-eight thousand, eight hundred sixty-eight".