1978236473 has 2 divisors, whose sum is σ = 1978236474. Its totient is φ = 1978236472.

The previous prime is 1978236427. The next prime is 1978236493. The reversal of 1978236473 is 3746328791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1820558224 + 157678249 = 42668^2 + 12557^2 .

It is an emirp because it is prime and its reverse (3746328791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1978236473 - 2⁸ = 1978236217 is a prime.

It is not a weakly prime, because it can be changed into another prime (1978236493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 989118236 + 989118237.

It is an arithmetic number, because the mean of its divisors is an integer number (989118237).

Almost surely, 2^1978236473 is an apocalyptic number.

It is an amenable number.

1978236473 is a deficient number, since it is larger than the sum of its proper divisors (1).

1978236473 is an equidigital number, since it uses as much as digits as its factorization.

1978236473 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1524096, while the sum is 50.

The square root of 1978236473 is about 44477.3703471777. The cubic root of 1978236473 is about 1255.3343179006.

The spelling of 1978236473 in words is "one billion, nine hundred seventy-eight million, two hundred thirty-six thousand, four hundred seventy-three".