780705073 has 2 divisors, whose sum is σ = 780705074. Its totient is φ = 780705072.

The previous prime is 780705047. The next prime is 780705089. The reversal of 780705073 is 370507087.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 616429584 + 164275489 = 24828^2 + 12817^2 .

It is a cyclic number.

It is not a de Polignac number, because 780705073 - 2¹⁷ = 780574001 is a prime.

It is a super-2 number, since 2×780705073² = 1219000822015870658, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (780705043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 390352536 + 390352537.

It is an arithmetic number, because the mean of its divisors is an integer number (390352537).

Almost surely, 2^780705073 is an apocalyptic number.

It is an amenable number.

780705073 is a deficient number, since it is larger than the sum of its proper divisors (1).

780705073 is an equidigital number, since it uses as much as digits as its factorization.

780705073 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 41160, while the sum is 37.

The square root of 780705073 is about 27941.1000678212. The cubic root of 780705073 is about 920.7936885088.

The spelling of 780705073 in words is "seven hundred eighty million, seven hundred five thousand, seventy-three".