1978872793 has 2 divisors, whose sum is σ = 1978872794. Its totient is φ = 1978872792.

The previous prime is 1978872773. The next prime is 1978872829. The reversal of 1978872793 is 3972788791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1092500809 + 886371984 = 33053^2 + 29772^2 .

It is a cyclic number.

It is not a de Polignac number, because 1978872793 - 2²⁹ = 1442001881 is a prime.

It is not a weakly prime, because it can be changed into another prime (1978872703) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 989436396 + 989436397.

It is an arithmetic number, because the mean of its divisors is an integer number (989436397).

Almost surely, 2^1978872793 is an apocalyptic number.

It is an amenable number.

1978872793 is a deficient number, since it is larger than the sum of its proper divisors (1).

1978872793 is an equidigital number, since it uses as much as digits as its factorization.

1978872793 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10668672, while the sum is 61.

The square root of 1978872793 is about 44484.5230726373. The cubic root of 1978872793 is about 1255.4689005138.

The spelling of 1978872793 in words is "one billion, nine hundred seventy-eight million, eight hundred seventy-two thousand, seven hundred ninety-three".