819859949 has 8 divisors (see below), whose sum is σ = 843232920. Its totient is φ = 796550976.

The previous prime is 819859939. The next prime is 819859951. The reversal of 819859949 is 949958918.

It can be written as a sum of positive squares in 4 ways, for example, as 170119849 + 649740100 = 13043^2 + 25490^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 819859949 - 2²⁰ = 818811373 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 819859891 and 819859900.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (819859919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10607 + ... + 41859.

It is an arithmetic number, because the mean of its divisors is an integer number (105404115).

Almost surely, 2^819859949 is an apocalyptic number.

It is an amenable number.

819859949 is a deficient number, since it is larger than the sum of its proper divisors (23372971).

819859949 is a wasteful number, since it uses less digits than its factorization.

819859949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31999.

The product of its digits is 8398080, while the sum is 62.

The square root of 819859949 is about 28633.1966255953. The cubic root of 819859949 is about 935.9368721426.

The spelling of 819859949 in words is "eight hundred nineteen million, eight hundred fifty-nine thousand, nine hundred forty-nine".