1780665041 has 2 divisors, whose sum is σ = 1780665042. Its totient is φ = 1780665040.

The previous prime is 1780665023. The next prime is 1780665043. The reversal of 1780665041 is 1405660871.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1765680400 + 14984641 = 42020^2 + 3871^2 .

It is a cyclic number.

It is not a de Polignac number, because 1780665041 - 2¹⁴ = 1780648657 is a prime.

Together with 1780665043, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1780664986 and 1780665004.

It is not a weakly prime, because it can be changed into another prime (1780665043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 890332520 + 890332521.

It is an arithmetic number, because the mean of its divisors is an integer number (890332521).

Almost surely, 2^1780665041 is an apocalyptic number.

It is an amenable number.

1780665041 is a deficient number, since it is larger than the sum of its proper divisors (1).

1780665041 is an equidigital number, since it uses as much as digits as its factorization.

1780665041 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 38.

The square root of 1780665041 is about 42197.9269751489. The cubic root of 1780665041 is about 1212.0691870248.

The spelling of 1780665041 in words is "one billion, seven hundred eighty million, six hundred sixty-five thousand, forty-one".