1978820067 has 12 divisors (see below), whose sum is σ = 3069190536. Its totient is φ = 1130754240.

The previous prime is 1978820059. The next prime is 1978820069. The reversal of 1978820067 is 7600288791.

It is not a de Polignac number, because 1978820067 - 2³ = 1978820059 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1978819998 and 1978820025.

It is not an unprimeable number, because it can be changed into a prime (1978820069) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 6730534 + ... + 6730827.

It is an arithmetic number, because the mean of its divisors is an integer number (255765878).

Almost surely, 2^1978820067 is an apocalyptic number.

1978820067 is a deficient number, since it is larger than the sum of its proper divisors (1090370469).

1978820067 is a wasteful number, since it uses less digits than its factorization.

1978820067 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13461378 (or 13461371 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 48.

The square root of 1978820067 is about 44483.9304356079. The cubic root of 1978820067 is about 1255.4577499838.

The spelling of 1978820067 in words is "one billion, nine hundred seventy-eight million, eight hundred twenty thousand, sixty-seven".