1973778885 has 36 divisors (see below), whose sum is σ = 3704645412. Its totient is φ = 971702784.

The previous prime is 1973778869. The next prime is 1973778893. The reversal of 1973778885 is 5888773791.

It can be written as a sum of positive squares in 6 ways, for example, as 280127169 + 1693651716 = 16737^2 + 41154^2 .

It is not a de Polignac number, because 1973778885 - 2⁴ = 1973778869 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 122164 + ... + 137373.

It is an arithmetic number, because the mean of its divisors is an integer number (102906817).

Almost surely, 2^1973778885 is an apocalyptic number.

1973778885 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1973778885 is a deficient number, since it is larger than the sum of its proper divisors (1730866527).

1973778885 is a wasteful number, since it uses less digits than its factorization.

1973778885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259574 (or 259558 counting only the distinct ones).

The product of its digits is 23708160, while the sum is 63.

The square root of 1973778885 is about 44427.2313452009. The cubic root of 1973778885 is about 1254.3907213284.

The spelling of 1973778885 in words is "one billion, nine hundred seventy-three million, seven hundred seventy-eight thousand, eight hundred eighty-five".