673557649 has 2 divisors, whose sum is σ = 673557650. Its totient is φ = 673557648.

The previous prime is 673557613. The next prime is 673557659. The reversal of 673557649 is 946755376.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 673039249 + 518400 = 25943^2 + 720^2 .

It is a cyclic number.

It is not a de Polignac number, because 673557649 - 2¹⁵ = 673524881 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 673557596 and 673557605.

It is not a weakly prime, because it can be changed into another prime (673557659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 336778824 + 336778825.

It is an arithmetic number, because the mean of its divisors is an integer number (336778825).

Almost surely, 2^673557649 is an apocalyptic number.

It is an amenable number.

673557649 is a deficient number, since it is larger than the sum of its proper divisors (1).

673557649 is an equidigital number, since it uses as much as digits as its factorization.

673557649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4762800, while the sum is 52.

The square root of 673557649 is about 25952.9892112643. The cubic root of 673557649 is about 876.5800670255.

The spelling of 673557649 in words is "six hundred seventy-three million, five hundred fifty-seven thousand, six hundred forty-nine".