978276821 has 8 divisors (see below), whose sum is σ = 987652224. Its totient is φ = 968914240.

The previous prime is 978276797. The next prime is 978276823. The reversal of 978276821 is 128672879.

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 978276821 - 2⁶ = 978276757 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 978276821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (978276823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 226916 + ... + 231186.

It is an arithmetic number, because the mean of its divisors is an integer number (123456528).

Almost surely, 2^978276821 is an apocalyptic number.

It is an amenable number.

978276821 is a deficient number, since it is larger than the sum of its proper divisors (9375403).

978276821 is a wasteful number, since it uses less digits than its factorization.

978276821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6411.

The product of its digits is 677376, while the sum is 50.

The square root of 978276821 is about 31277.4171088343. The cubic root of 978276821 is about 992.7058652922.

The spelling of 978276821 in words is "nine hundred seventy-eight million, two hundred seventy-six thousand, eight hundred twenty-one".