1978694485 has 16 divisors (see below), whose sum is σ = 2608076160. Its totient is φ = 1434438720.

The previous prime is 1978694467. The next prime is 1978694491. The reversal of 1978694485 is 5844968791.

It is not a de Polignac number, because 1978694485 - 2⁵ = 1978694453 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 450606 + ... + 454975.

It is an arithmetic number, because the mean of its divisors is an integer number (163004760).

Almost surely, 2^1978694485 is an apocalyptic number.

It is an amenable number.

1978694485 is a deficient number, since it is larger than the sum of its proper divisors (629381675).

1978694485 is a wasteful number, since it uses less digits than its factorization.

1978694485 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 905628.

The product of its digits is 17418240, while the sum is 61.

The square root of 1978694485 is about 44482.5188697762. The cubic root of 1978694485 is about 1255.4311910202.

The spelling of 1978694485 in words is "one billion, nine hundred seventy-eight million, six hundred ninety-four thousand, four hundred eighty-five".