1978236396 has 18 divisors (see below), whose sum is σ = 5000542092. Its totient is φ = 659412120.

The previous prime is 1978236389. The next prime is 1978236427. The reversal of 1978236396 is 6936328791.

1978236396 is a `hidden beast` number, since 19 + 7 + 8 + 236 + 396 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 27475470 + ... + 27475541.

It is an arithmetic number, because the mean of its divisors is an integer number (277807894).

Almost surely, 2^1978236396 is an apocalyptic number.

It is an amenable number.

1978236396 is an abundant number, since it is smaller than the sum of its proper divisors (3022305696).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1978236396 is a wasteful number, since it uses less digits than its factorization.

1978236396 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54951021 (or 54951016 counting only the distinct ones).

The product of its digits is 2939328, while the sum is 54.

The square root of 1978236396 is about 44477.3694815689. The cubic root of 1978236396 is about 1255.3343016133.

The spelling of 1978236396 in words is "one billion, nine hundred seventy-eight million, two hundred thirty-six thousand, three hundred ninety-six".