67258791649 has 9 divisors (see below), whose sum is σ = 78241930707. Its totient is φ = 57648836784.

The previous prime is 67258791629. The next prime is 67258791673. The reversal of 67258791649 is 94619785276.

The square root of 67258791649 is 259343.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 9812289249 + 57446502400 = 99057^2 + 239680^2 .

It is not a de Polignac number, because 67258791649 - 2⁵ = 67258791617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67258791629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1796877 + ... + 1833925.

Almost surely, 2^67258791649 is an apocalyptic number.

67258791649 is the 259343-rd square number.

67258791649 is the 129672-nd centered octagonal number.

It is an amenable number.

67258791649 is a deficient number, since it is larger than the sum of its proper divisors (10983139058).

67258791649 is an frugal number, since it uses more digits than its factorization.

67258791649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74112 (or 37056 counting only the distinct ones).

The product of its digits is 45722880, while the sum is 64.

Multiplying 67258791649 by its sum of digits (64), we get a square (4304562665536 = 2074744²).

The spelling of 67258791649 in words is "sixty-seven billion, two hundred fifty-eight million, seven hundred ninety-one thousand, six hundred forty-nine".