91288012 has 24 divisors (see below), whose sum is σ = 168588000. Its totient is φ = 43165056.

The previous prime is 91288009. The next prime is 91288019. The reversal of 91288012 is 21088219.

It is a happy number.

It is a super-2 number, since 2×91288012² = 16667002269824288, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91288019) 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, 2614 + ... + 13762.

It is an arithmetic number, because the mean of its divisors is an integer number (7024500).

Almost surely, 2^91288012 is an apocalyptic number.

91288012 is a gapful number since it is divisible by the number (92) formed by its first and last digit.

It is an amenable number.

91288012 is a deficient number, since it is larger than the sum of its proper divisors (77299988).

91288012 is a wasteful number, since it uses less digits than its factorization.

91288012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11265 (or 11263 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 91288012 is about 9554.4760191232. The cubic root of 91288012 is about 450.2681726639.

The spelling of 91288012 in words is "ninety-one million, two hundred eighty-eight thousand, twelve".