1780434978 has 16 divisors (see below), whose sum is σ = 4069565760. Its totient is φ = 508695696.

The previous prime is 1780434967. The next prime is 1780435001. The reversal of 1780434978 is 8794340871.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1780434978.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21195613 + ... + 21195696.

It is an arithmetic number, because the mean of its divisors is an integer number (254347860).

Almost surely, 2^1780434978 is an apocalyptic number.

1780434978 is an abundant number, since it is smaller than the sum of its proper divisors (2289130782).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1780434978 is a wasteful number, since it uses less digits than its factorization.

1780434978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42391321.

The product of its (nonzero) digits is 1354752, while the sum is 51.

The square root of 1780434978 is about 42195.2008882527. The cubic root of 1780434978 is about 1212.0169847526.

The spelling of 1780434978 in words is "one billion, seven hundred eighty million, four hundred thirty-four thousand, nine hundred seventy-eight".