820081449 has 16 divisors (see below), whose sum is σ = 1325384640. Its totient is φ = 497018880.

The previous prime is 820081429. The next prime is 820081463. The reversal of 820081449 is 944180028.

820081449 is a `hidden beast` number, since 8 + 200 + 8 + 1 + 449 = 666.

It is not a de Polignac number, because 820081449 - 2⁷ = 820081321 is a prime.

It is not an unprimeable number, because it can be changed into a prime (820081429) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1380312 + ... + 1380905.

It is an arithmetic number, because the mean of its divisors is an integer number (82836540).

Almost surely, 2^820081449 is an apocalyptic number.

It is an amenable number.

820081449 is a deficient number, since it is larger than the sum of its proper divisors (505303191).

820081449 is a wasteful number, since it uses less digits than its factorization.

820081449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2761237 (or 2761231 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 820081449 is about 28637.0642524683. The cubic root of 820081449 is about 936.0211513136.

The spelling of 820081449 in words is "eight hundred twenty million, eighty-one thousand, four hundred forty-nine".