1978946205 has 16 divisors (see below), whose sum is σ = 3175447104. Its totient is φ = 1052393600.

The previous prime is 1978946191. The next prime is 1978946209. The reversal of 1978946205 is 5026498791.

It is not a de Polignac number, because 1978946205 - 2⁵ = 1978946173 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1978946209) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 184896 + ... + 195305.

It is an arithmetic number, because the mean of its divisors is an integer number (198465444).

Almost surely, 2^1978946205 is an apocalyptic number.

1978946205 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1978946205 is a deficient number, since it is larger than the sum of its proper divisors (1196500899).

1978946205 is a wasteful number, since it uses less digits than its factorization.

1978946205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380556.

The product of its (nonzero) digits is 1088640, while the sum is 51.

The square root of 1978946205 is about 44485.3482058981. The cubic root of 1978946205 is about 1255.4844254031.

The spelling of 1978946205 in words is "one billion, nine hundred seventy-eight million, nine hundred forty-six thousand, two hundred five".