83978421 has 8 divisors (see below), whose sum is σ = 112014144. Its totient is φ = 55964160.

The previous prime is 83978413. The next prime is 83978431. The reversal of 83978421 is 12487938.

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

It is not a de Polignac number, because 83978421 - 2³ = 83978413 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (83978431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10320 + ... + 16566.

It is an arithmetic number, because the mean of its divisors is an integer number (14001768).

Almost surely, 2^83978421 is an apocalyptic number.

It is an amenable number.

83978421 is a deficient number, since it is larger than the sum of its proper divisors (28035723).

83978421 is a wasteful number, since it uses less digits than its factorization.

83978421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10731.

The product of its digits is 96768, while the sum is 42.

The square root of 83978421 is about 9163.9740833331. The cubic root of 83978421 is about 437.9144085375.

The spelling of 83978421 in words is "eighty-three million, nine hundred seventy-eight thousand, four hundred twenty-one".