781443624049 has 9 divisors (see below), whose sum is σ = 858952853689. Its totient is φ = 710394454660.

The previous prime is 781443624047. The next prime is 781443624107. The reversal of 781443624049 is 940426344187.

The square root of 781443624049 is 883993.

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

It is not a de Polignac number, because 781443624049 - 2¹ = 781443624047 is a prime.

It is a super-2 number, since 2×781443624049² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 781443623987 and 781443624005.

It is not an unprimeable number, because it can be changed into a prime (781443624047) 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, 9683742 + ... + 9764104.

Almost surely, 2^781443624049 is an apocalyptic number.

781443624049 is the 883993-rd square number.

781443624049 is the 441997-th centered octagonal number.

It is an amenable number.

781443624049 is a deficient number, since it is larger than the sum of its proper divisors (77509229640).

781443624049 is an frugal number, since it uses more digits than its factorization.

781443624049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160748 (or 80374 counting only the distinct ones).

The product of its (nonzero) digits is 4644864, while the sum is 52.

The spelling of 781443624049 in words is "seven hundred eighty-one billion, four hundred forty-three million, six hundred twenty-four thousand, forty-nine".