91221003 has 36 divisors (see below), whose sum is σ = 139417200. Its totient is φ = 57451680.

The previous prime is 91221001. The next prime is 91221007. The reversal of 91221003 is 30012219.

It is a happy number.

It is not a de Polignac number, because 91221003 - 2¹ = 91221001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91221001) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 458298 + ... + 458496.

It is an arithmetic number, because the mean of its divisors is an integer number (3872700).

Almost surely, 2^91221003 is an apocalyptic number.

91221003 is a gapful number since it is divisible by the number (93) formed by its first and last digit.

91221003 is a deficient number, since it is larger than the sum of its proper divisors (48196197).

91221003 is a wasteful number, since it uses less digits than its factorization.

91221003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320 (or 286 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 91221003 is about 9550.9686943262. The cubic root of 91221003 is about 450.1579741657.

The spelling of 91221003 in words is "ninety-one million, two hundred twenty-one thousand, three".