215693 has 2 divisors, whose sum is σ = 215694. Its totient is φ = 215692.

The previous prime is 215689. The next prime is 215723. The reversal of 215693 is 396512.

215693 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 209764 + 5929 = 458^2 + 77^2 .

It is a cyclic number.

It is not a de Polignac number, because 215693 - 2² = 215689 is a prime.

It is a plaindrome in base 9.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107846 + 107847.

It is an arithmetic number, because the mean of its divisors is an integer number (107847).

2²¹⁵⁶⁹³ is an apocalyptic number.

It is an amenable number.

215693 is a deficient number, since it is larger than the sum of its proper divisors (1).

215693 is an equidigital number, since it uses as much as digits as its factorization.

215693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1620, while the sum is 26.

The square root of 215693 is about 464.4276046921. The cubic root of 215693 is about 59.9715605962.

The spelling of 215693 in words is "two hundred fifteen thousand, six hundred ninety-three".