1786978449 has 16 divisors (see below), whose sum is σ = 2653136640. Its totient is φ = 1188726480.

The previous prime is 1786978441. The next prime is 1786978451. The reversal of 1786978449 is 9448796871.

It is not a de Polignac number, because 1786978449 - 2³ = 1786978441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1786978441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59337 + ... + 84230.

It is an arithmetic number, because the mean of its divisors is an integer number (165821040).

Almost surely, 2^1786978449 is an apocalyptic number.

It is an amenable number.

1786978449 is a deficient number, since it is larger than the sum of its proper divisors (866158191).

1786978449 is a wasteful number, since it uses less digits than its factorization.

1786978449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144037 (or 144031 counting only the distinct ones).

The product of its digits is 24385536, while the sum is 63.

The square root of 1786978449 is about 42272.6678718058. The cubic root of 1786978449 is about 1213.4999747892.

The spelling of 1786978449 in words is "one billion, seven hundred eighty-six million, nine hundred seventy-eight thousand, four hundred forty-nine".