819990049 has 4 divisors (see below), whose sum is σ = 863147440. Its totient is φ = 776832660.

The previous prime is 819990023. The next prime is 819990077. The reversal of 819990049 is 940099918.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 819990049 - 2¹⁹ = 819465761 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 819989984 and 819990011.

It is not an unprimeable number, because it can be changed into a prime (819990649) 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, 21578667 + ... + 21578704.

It is an arithmetic number, because the mean of its divisors is an integer number (215786860).

Almost surely, 2^819990049 is an apocalyptic number.

It is an amenable number.

819990049 is a deficient number, since it is larger than the sum of its proper divisors (43157391).

819990049 is a wasteful number, since it uses less digits than its factorization.

819990049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43157390.

The product of its (nonzero) digits is 209952, while the sum is 49.

The square root of 819990049 is about 28635.4683740287. The cubic root of 819990049 is about 935.9863761044.

The spelling of 819990049 in words is "eight hundred nineteen million, nine hundred ninety thousand, forty-nine".