780064381 has 2 divisors, whose sum is σ = 780064382. Its totient is φ = 780064380.

The previous prime is 780064379. The next prime is 780064393. The reversal of 780064381 is 183460087.

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., 744471225 + 35593156 = 27285^2 + 5966^2 .

It is a cyclic number.

It is not a de Polignac number, because 780064381 - 2¹ = 780064379 is a prime.

It is a super-2 number, since 2×780064381² = 1217000877009826322, which contains 22 as substring.

Together with 780064379, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 780064381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (780064321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 390032190 + 390032191.

It is an arithmetic number, because the mean of its divisors is an integer number (390032191).

Almost surely, 2^780064381 is an apocalyptic number.

It is an amenable number.

780064381 is a deficient number, since it is larger than the sum of its proper divisors (1).

780064381 is an equidigital number, since it uses as much as digits as its factorization.

780064381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32256, while the sum is 37.

The square root of 780064381 is about 27929.6326685476. The cubic root of 780064381 is about 920.5417339509.

The spelling of 780064381 in words is "seven hundred eighty million, sixty-four thousand, three hundred eighty-one".