83656921 has 2 divisors, whose sum is σ = 83656922. Its totient is φ = 83656920.

The previous prime is 83656919. The next prime is 83656961. The reversal of 83656921 is 12965638.

It is an a-pointer prime, because the next prime (83656961) can be obtained adding 83656921 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60279696 + 23377225 = 7764^2 + 4835^2 .

It is a cyclic number.

It is not a de Polignac number, because 83656921 - 2¹ = 83656919 is a prime.

Together with 83656919, it forms a pair of twin primes.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (83656901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41828460 + 41828461.

It is an arithmetic number, because the mean of its divisors is an integer number (41828461).

Almost surely, 2^83656921 is an apocalyptic number.

It is an amenable number.

83656921 is a deficient number, since it is larger than the sum of its proper divisors (1).

83656921 is an equidigital number, since it uses as much as digits as its factorization.

83656921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 77760, while the sum is 40.

The square root of 83656921 is about 9146.4157460723. The cubic root of 83656921 is about 437.3548618974.

The spelling of 83656921 in words is "eighty-three million, six hundred fifty-six thousand, nine hundred twenty-one".