204861619 has 2 divisors, whose sum is σ = 204861620. Its totient is φ = 204861618.

The previous prime is 204861617. The next prime is 204861623. The reversal of 204861619 is 916168402.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 204861619 - 2¹ = 204861617 is a prime.

It is a super-2 number, since 2×204861619² = 83936565878602322, which contains 22 as substring.

Together with 204861617, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (204861617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102430809 + 102430810.

It is an arithmetic number, because the mean of its divisors is an integer number (102430810).

Almost surely, 2^204861619 is an apocalyptic number.

204861619 is a deficient number, since it is larger than the sum of its proper divisors (1).

204861619 is an equidigital number, since it uses as much as digits as its factorization.

204861619 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 204861619 is about 14312.9877733477. The cubic root of 204861619 is about 589.5041500882.

The spelling of 204861619 in words is "two hundred four million, eight hundred sixty-one thousand, six hundred nineteen".