1978780457233 has 4 divisors (see below), whose sum is σ = 1978805721060. Its totient is φ = 1978755193408.

The previous prime is 1978780457081. The next prime is 1978780457257. The reversal of 1978780457233 is 3327540878791.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1835667297424 + 143113159809 = 1354868^2 + 378303^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1978780457233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1978780457833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12514060 + ... + 12671197.

It is an arithmetic number, because the mean of its divisors is an integer number (494701430265).

Almost surely, 2^{1978780457233} is an apocalyptic number.

It is an amenable number.

1978780457233 is a deficient number, since it is larger than the sum of its proper divisors (25263827).

1978780457233 is an equidigital number, since it uses as much as digits as its factorization.

1978780457233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25263826.

The product of its (nonzero) digits is 71124480, while the sum is 64.

The spelling of 1978780457233 in words is "one trillion, nine hundred seventy-eight billion, seven hundred eighty million, four hundred fifty-seven thousand, two hundred thirty-three".