219238661 has 2 divisors, whose sum is σ = 219238662. Its totient is φ = 219238660.

The previous prime is 219238633. The next prime is 219238709. The reversal of 219238661 is 166832912.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 219217636 + 21025 = 14806^2 + 145^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-219238661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (219238601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109619330 + 109619331.

It is an arithmetic number, because the mean of its divisors is an integer number (109619331).

Almost surely, 2^219238661 is an apocalyptic number.

It is an amenable number.

219238661 is a deficient number, since it is larger than the sum of its proper divisors (1).

219238661 is an equidigital number, since it uses as much as digits as its factorization.

219238661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31104, while the sum is 38.

The square root of 219238661 is about 14806.7099991862. The cubic root of 219238661 is about 602.9838961915.

The spelling of 219238661 in words is "two hundred nineteen million, two hundred thirty-eight thousand, six hundred sixty-one".