215554243 has 2 divisors, whose sum is σ = 215554244. Its totient is φ = 215554242.

The previous prime is 215554231. The next prime is 215554247. The reversal of 215554243 is 342455512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 215554243 - 2⁵ = 215554211 is a prime.

It is not a weakly prime, because it can be changed into another prime (215554247) 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, 107777121 + 107777122.

It is an arithmetic number, because the mean of its divisors is an integer number (107777122).

Almost surely, 2^215554243 is an apocalyptic number.

215554243 is a deficient number, since it is larger than the sum of its proper divisors (1).

215554243 is an equidigital number, since it uses as much as digits as its factorization.

215554243 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24000, while the sum is 31.

The square root of 215554243 is about 14681.7656635706. The cubic root of 215554243 is about 599.5869777900.

The spelling of 215554243 in words is "two hundred fifteen million, five hundred fifty-four thousand, two hundred forty-three".