778642223 has 2 divisors, whose sum is σ = 778642224. Its totient is φ = 778642222.

The previous prime is 778642219. The next prime is 778642231. The reversal of 778642223 is 322246877.

It is a weak prime.

It is an emirp because it is prime and its reverse (322246877) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 778642223 - 2² = 778642219 is a prime.

It is a super-2 number, since 2×778642223² = 1212567422876763458, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (778642213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 389321111 + 389321112.

It is an arithmetic number, because the mean of its divisors is an integer number (389321112).

Almost surely, 2^778642223 is an apocalyptic number.

778642223 is a deficient number, since it is larger than the sum of its proper divisors (1).

778642223 is an equidigital number, since it uses as much as digits as its factorization.

778642223 is an evil number, because the sum of its binary digits is even.

The product of its digits is 225792, while the sum is 41.

The square root of 778642223 is about 27904.1613921651. The cubic root of 778642223 is about 919.9819715276.

The spelling of 778642223 in words is "seven hundred seventy-eight million, six hundred forty-two thousand, two hundred twenty-three".