780649 has 2 divisors, whose sum is σ = 780650. Its totient is φ = 780648.

The previous prime is 780631. The next prime is 780667. The reversal of 780649 is 946087.

It is a balanced prime because it is at equal distance from previous prime (780631) and next prime (780667).

It can be written as a sum of positive squares in only one way, i.e., 753424 + 27225 = 868^2 + 165^2 .

It is a cyclic number.

It is not a de Polignac number, because 780649 - 2¹⁷ = 649577 is a prime.

It is a super-2 number, since 2×780649² = 1218825722402, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (780679) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 390324 + 390325.

It is an arithmetic number, because the mean of its divisors is an integer number (390325).

2⁷⁸⁰⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

780649 is a deficient number, since it is larger than the sum of its proper divisors (1).

780649 is an equidigital number, since it uses as much as digits as its factorization.

780649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 780649 is about 883.5434341333. The cubic root of 780649 is about 92.0771643094.

It can be divided in two parts, 7 and 80649, that added together give a square (80656 = 284²).

The spelling of 780649 in words is "seven hundred eighty thousand, six hundred forty-nine".