321996091 has 2 divisors, whose sum is σ = 321996092. Its totient is φ = 321996090.

The previous prime is 321996061. The next prime is 321996109. The reversal of 321996091 is 190699123.

Together with next prime (321996109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 321996091 - 2²¹ = 319898939 is a prime.

It is not a weakly prime, because it can be changed into another prime (321996061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160998045 + 160998046.

It is an arithmetic number, because the mean of its divisors is an integer number (160998046).

Almost surely, 2^321996091 is an apocalyptic number.

321996091 is a deficient number, since it is larger than the sum of its proper divisors (1).

321996091 is an equidigital number, since it uses as much as digits as its factorization.

321996091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26244, while the sum is 40.

The square root of 321996091 is about 17944.2495245691. The cubic root of 321996091 is about 685.4096265933.

The spelling of 321996091 in words is "three hundred twenty-one million, nine hundred ninety-six thousand, ninety-one".