2978021993 has 2 divisors, whose sum is σ = 2978021994. Its totient is φ = 2978021992.

The previous prime is 2978021957. The next prime is 2978022049. The reversal of 2978021993 is 3991208792.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2415525904 + 562496089 = 49148^2 + 23717^2 .

It is a cyclic number.

It is not a de Polignac number, because 2978021993 - 2²⁶ = 2910913129 is a prime.

It is a super-2 number, since 2×2978021993² = 17737229981583384098, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2978026993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1489010996 + 1489010997.

It is an arithmetic number, because the mean of its divisors is an integer number (1489010997).

Almost surely, 2^2978021993 is an apocalyptic number.

It is an amenable number.

2978021993 is a deficient number, since it is larger than the sum of its proper divisors (1).

2978021993 is an equidigital number, since it uses as much as digits as its factorization.

2978021993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 489888, while the sum is 50.

The square root of 2978021993 is about 54571.2561061224. The cubic root of 2978021993 is about 1438.7189598937.

The spelling of 2978021993 in words is "two billion, nine hundred seventy-eight million, twenty-one thousand, nine hundred ninety-three".