1982778369 has 64 divisors (see below), whose sum is σ = 3188118528. Its totient is φ = 1080288000.

The previous prime is 1982778353. The next prime is 1982778379. The reversal of 1982778369 is 9638772891.

It is not a de Polignac number, because 1982778369 - 2⁴ = 1982778353 is a prime.

It is a super-2 number, since 2×1982778369² = 7862820121148600322, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1982778349) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2902702 + ... + 2903384.

It is an arithmetic number, because the mean of its divisors is an integer number (49814352).

Almost surely, 2^1982778369 is an apocalyptic number.

It is an amenable number.

1982778369 is a deficient number, since it is larger than the sum of its proper divisors (1205340159).

1982778369 is a wasteful number, since it uses less digits than its factorization.

1982778369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 878.

The product of its digits is 9144576, while the sum is 60.

The square root of 1982778369 is about 44528.3995782467. The cubic root of 1982778369 is about 1256.2943042418.

The spelling of 1982778369 in words is "one billion, nine hundred eighty-two million, seven hundred seventy-eight thousand, three hundred sixty-nine".