819068749 has 4 divisors (see below), whose sum is σ = 819474460. Its totient is φ = 818663040.

The previous prime is 819068743. The next prime is 819068753. The reversal of 819068749 is 947860918.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 947860918 = 2 ⋅473930459.

It can be written as a sum of positive squares in 2 ways, for example, as 706602724 + 112466025 = 26582^2 + 10605^2 .

It is a cyclic number.

It is not a de Polignac number, because 819068749 - 2¹⁵ = 819035981 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 819068696 and 819068705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (819068743) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 199812 + ... + 203869.

It is an arithmetic number, because the mean of its divisors is an integer number (204868615).

Almost surely, 2^819068749 is an apocalyptic number.

It is an amenable number.

819068749 is a deficient number, since it is larger than the sum of its proper divisors (405711).

819068749 is a wasteful number, since it uses less digits than its factorization.

819068749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405710.

The product of its (nonzero) digits is 870912, while the sum is 52.

The square root of 819068749 is about 28619.3771595400. The cubic root of 819068749 is about 935.6357021721.

The spelling of 819068749 in words is "eight hundred nineteen million, sixty-eight thousand, seven hundred forty-nine".