20955331 has 2 divisors, whose sum is σ = 20955332. Its totient is φ = 20955330.

The previous prime is 20955293. The next prime is 20955343. The reversal of 20955331 is 13355902.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20955331 - 2⁹ = 20954819 is a prime.

It is a super-2 number, since 2×20955331² = 878251794639122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20955331.

It is not a weakly prime, because it can be changed into another prime (20955031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10477665 + 10477666.

It is an arithmetic number, because the mean of its divisors is an integer number (10477666).

Almost surely, 2^20955331 is an apocalyptic number.

20955331 is a deficient number, since it is larger than the sum of its proper divisors (1).

20955331 is an equidigital number, since it uses as much as digits as its factorization.

20955331 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4050, while the sum is 28.

The square root of 20955331 is about 4577.6993129737. The cubic root of 20955331 is about 275.6966622931.

The spelling of 20955331 in words is "twenty million, nine hundred fifty-five thousand, three hundred thirty-one".