91154221 has 16 divisors (see below), whose sum is σ = 104198400. Its totient is φ = 79222528.

The previous prime is 91154201. The next prime is 91154227. The reversal of 91154221 is 12245119.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 91154221 - 2²¹ = 89057069 is a prime.

It is a super-2 number, since 2×91154221² = 16618184012233682, which 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 (91154227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7320 + ... + 15358.

It is an arithmetic number, because the mean of its divisors is an integer number (6512400).

Almost surely, 2^91154221 is an apocalyptic number.

It is an amenable number.

91154221 is a deficient number, since it is larger than the sum of its proper divisors (13044179).

91154221 is a wasteful number, since it uses less digits than its factorization.

91154221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8108.

The product of its digits is 720, while the sum is 25.

The square root of 91154221 is about 9547.4719690607. The cubic root of 91154221 is about 450.0480952710.

The spelling of 91154221 in words is "ninety-one million, one hundred fifty-four thousand, two hundred twenty-one".