1978797978797 has 8 divisors (see below), whose sum is σ = 2008403448576. Its totient is φ = 1949194602432.

The previous prime is 1978797978739. The next prime is 1978797978809. The reversal of 1978797978797 is 7978797978791.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1978797978797 - 2¹⁰ = 1978797977773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1978797978497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1435733 + ... + 2453349.

It is an arithmetic number, because the mean of its divisors is an integer number (251050431072).

Almost surely, 2^{1978797978797} is an apocalyptic number.

It is an amenable number.

1978797978797 is a deficient number, since it is larger than the sum of its proper divisors (29605469779).

1978797978797 is a wasteful number, since it uses less digits than its factorization.

1978797978797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1046707.

The product of its digits is 49401285696, while the sum is 95.

The spelling of 1978797978797 in words is "one trillion, nine hundred seventy-eight billion, seven hundred ninety-seven million, nine hundred seventy-eight thousand, seven hundred ninety-seven".