91056921 has 16 divisors (see below), whose sum is σ = 123002880. Its totient is φ = 59913360.

The previous prime is 91056919. The next prime is 91056923. The reversal of 91056921 is 12965019.

It is an interprime number because it is at equal distance from previous prime (91056919) and next prime (91056923).

It is not a de Polignac number, because 91056921 - 2¹ = 91056919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91056923) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87120 + ... + 88158.

It is an arithmetic number, because the mean of its divisors is an integer number (7687680).

Almost surely, 2^91056921 is an apocalyptic number.

It is an amenable number.

91056921 is a deficient number, since it is larger than the sum of its proper divisors (31945959).

91056921 is a wasteful number, since it uses less digits than its factorization.

91056921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1396.

The product of its (nonzero) digits is 4860, while the sum is 33.

The square root of 91056921 is about 9542.3750188305. The cubic root of 91056921 is about 449.8879078834.

The spelling of 91056921 in words is "ninety-one million, fifty-six thousand, nine hundred twenty-one".