1980840965 has 8 divisors (see below), whose sum is σ = 2379239160. Its totient is φ = 1583186112.

The previous prime is 1980840931. The next prime is 1980840989. The reversal of 1980840965 is 5690480891.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 384199201 + 1596641764 = 19601^2 + 39958^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1980840965 is a prime.

It is a super-4 number, since 4×1980840965⁴ (a number of 38 digits) contains 4444 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 179954 + ... + 190643.

It is an arithmetic number, because the mean of its divisors is an integer number (297404895).

Almost surely, 2^1980840965 is an apocalyptic number.

It is an amenable number.

1980840965 is a deficient number, since it is larger than the sum of its proper divisors (398398195).

1980840965 is a wasteful number, since it uses less digits than its factorization.

1980840965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371671.

The product of its (nonzero) digits is 622080, while the sum is 50.

The square root of 1980840965 is about 44506.6395608565. The cubic root of 1980840965 is about 1255.8849892407.

The spelling of 1980840965 in words is "one billion, nine hundred eighty million, eight hundred forty thousand, nine hundred sixty-five".