978694920391 has 8 divisors (see below), whose sum is σ = 985899275424. Its totient is φ = 971491443840.

The previous prime is 978694920353. The next prime is 978694920397. The reversal of 978694920391 is 193029496879.

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 978694920391 - 2²³ = 978686531783 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 (978694920397) 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, 2107086 + ... + 2529268.

It is an arithmetic number, because the mean of its divisors is an integer number (123237409428).

Almost surely, 2^978694920391 is an apocalyptic number.

978694920391 is a deficient number, since it is larger than the sum of its proper divisors (7204355033).

978694920391 is a wasteful number, since it uses less digits than its factorization.

978694920391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439241.

The product of its (nonzero) digits is 52907904, while the sum is 67.

The spelling of 978694920391 in words is "nine hundred seventy-eight billion, six hundred ninety-four million, nine hundred twenty thousand, three hundred ninety-one".