221859697 has 2 divisors, whose sum is σ = 221859698. Its totient is φ = 221859696.

The previous prime is 221859691. The next prime is 221859761. The reversal of 221859697 is 796958122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 220344336 + 1515361 = 14844^2 + 1231^2 .

It is a cyclic number.

It is not a de Polignac number, because 221859697 - 2³ = 221859689 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221859697.

It is not a weakly prime, because it can be changed into another prime (221859691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110929848 + 110929849.

It is an arithmetic number, because the mean of its divisors is an integer number (110929849).

Almost surely, 2^221859697 is an apocalyptic number.

It is an amenable number.

221859697 is a deficient number, since it is larger than the sum of its proper divisors (1).

221859697 is an equidigital number, since it uses as much as digits as its factorization.

221859697 is an evil number, because the sum of its binary digits is even.

The product of its digits is 544320, while the sum is 49.

The square root of 221859697 is about 14894.9554212156. The cubic root of 221859697 is about 605.3773089808.

The spelling of 221859697 in words is "two hundred twenty-one million, eight hundred fifty-nine thousand, six hundred ninety-seven".