781120673 has 2 divisors, whose sum is σ = 781120674. Its totient is φ = 781120672.

The previous prime is 781120663. The next prime is 781120679. The reversal of 781120673 is 376021187.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 768786529 + 12334144 = 27727^2 + 3512^2 .

It is a cyclic number.

It is not a de Polignac number, because 781120673 - 2⁴ = 781120657 is a prime.

It is a super-2 number, since 2×781120673² = 1220299011575945858, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (781120679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 390560336 + 390560337.

It is an arithmetic number, because the mean of its divisors is an integer number (390560337).

Almost surely, 2^781120673 is an apocalyptic number.

It is an amenable number.

781120673 is a deficient number, since it is larger than the sum of its proper divisors (1).

781120673 is an equidigital number, since it uses as much as digits as its factorization.

781120673 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14112, while the sum is 35.

The square root of 781120673 is about 27948.5361512906. The cubic root of 781120673 is about 920.9570510831.

The spelling of 781120673 in words is "seven hundred eighty-one million, one hundred twenty thousand, six hundred seventy-three".