1981952109 has 12 divisors (see below), whose sum is σ = 2955169152. Its totient is φ = 1278678600.

The previous prime is 1981952069. The next prime is 1981952197. The reversal of 1981952109 is 9012591891.

It is not a de Polignac number, because 1981952109 - 2¹² = 1981948013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1981952309) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3551607 + ... + 3552164.

It is an arithmetic number, because the mean of its divisors is an integer number (246264096).

Almost surely, 2^1981952109 is an apocalyptic number.

It is an amenable number.

1981952109 is a deficient number, since it is larger than the sum of its proper divisors (973217043).

1981952109 is a wasteful number, since it uses less digits than its factorization.

1981952109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7103808 (or 7103805 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 45.

The square root of 1981952109 is about 44519.1207123411. The cubic root of 1981952109 is about 1256.1197730605.

The spelling of 1981952109 in words is "one billion, nine hundred eighty-one million, nine hundred fifty-two thousand, one hundred nine".