219408997 has 2 divisors, whose sum is σ = 219408998. Its totient is φ = 219408996.

The previous prime is 219408989. The next prime is 219409013. The reversal of 219408997 is 799804912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 129367876 + 90041121 = 11374^2 + 9489^2 .

It is a cyclic number.

It is not a de Polignac number, because 219408997 - 2³ = 219408989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 219408997.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (219408967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109704498 + 109704499.

It is an arithmetic number, because the mean of its divisors is an integer number (109704499).

Almost surely, 2^219408997 is an apocalyptic number.

It is an amenable number.

219408997 is a deficient number, since it is larger than the sum of its proper divisors (1).

219408997 is an equidigital number, since it uses as much as digits as its factorization.

219408997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 326592, while the sum is 49.

The square root of 219408997 is about 14812.4608691466. The cubic root of 219408997 is about 603.1400171908.

The spelling of 219408997 in words is "two hundred nineteen million, four hundred eight thousand, nine hundred ninety-seven".