1978272193 has 4 divisors (see below), whose sum is σ = 1979442388. Its totient is φ = 1977102000.

The previous prime is 1978272173. The next prime is 1978272199. The reversal of 1978272193 is 3912728791.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3912728791 = 523 ⋅7481317.

It can be written as a sum of positive squares in 2 ways, for example, as 599858064 + 1378414129 = 24492^2 + 37127^2 .

It is a cyclic number.

It is not a de Polignac number, because 1978272193 - 2²⁹ = 1441401281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1978272199) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 582558 + ... + 585943.

It is an arithmetic number, because the mean of its divisors is an integer number (494860597).

Almost surely, 2^1978272193 is an apocalyptic number.

It is an amenable number.

1978272193 is a deficient number, since it is larger than the sum of its proper divisors (1170195).

1978272193 is a wasteful number, since it uses less digits than its factorization.

1978272193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1170194.

The product of its digits is 381024, while the sum is 49.

The square root of 1978272193 is about 44477.7718978818. The cubic root of 1978272193 is about 1255.3418734975.

The spelling of 1978272193 in words is "one billion, nine hundred seventy-eight million, two hundred seventy-two thousand, one hundred ninety-three".