83931921 has 6 divisors (see below), whose sum is σ = 121235010. Its totient is φ = 55954608.

The previous prime is 83931917. The next prime is 83931929. The reversal of 83931921 is 12913938.

It can be written as a sum of positive squares in only one way, i.e., 83010321 + 921600 = 9111^2 + 960^2 .

It is not a de Polignac number, because 83931921 - 2² = 83931917 is a prime.

It is not an unprimeable number, because it can be changed into a prime (83931929) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4662876 + ... + 4662893.

It is an arithmetic number, because the mean of its divisors is an integer number (20205835).

Almost surely, 2^83931921 is an apocalyptic number.

It is an amenable number.

83931921 is a deficient number, since it is larger than the sum of its proper divisors (37303089).

83931921 is a wasteful number, since it uses less digits than its factorization.

83931921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9325775 (or 9325772 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 83931921 is about 9161.4366231503. The cubic root of 83931921 is about 437.8335672160.

The spelling of 83931921 in words is "eighty-three million, nine hundred thirty-one thousand, nine hundred twenty-one".