82979621 has 2 divisors, whose sum is σ = 82979622. Its totient is φ = 82979620.

The previous prime is 82979597. The next prime is 82979639. The reversal of 82979621 is 12697928.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43428100 + 39551521 = 6590^2 + 6289^2 .

It is a cyclic number.

It is not a de Polignac number, because 82979621 - 2⁶ = 82979557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82979671) 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, 41489810 + 41489811.

It is an arithmetic number, because the mean of its divisors is an integer number (41489811).

Almost surely, 2^82979621 is an apocalyptic number.

It is an amenable number.

82979621 is a deficient number, since it is larger than the sum of its proper divisors (1).

82979621 is an equidigital number, since it uses as much as digits as its factorization.

82979621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 44.

The square root of 82979621 is about 9109.3150675558. The cubic root of 82979621 is about 436.1713635653.

The spelling of 82979621 in words is "eighty-two million, nine hundred seventy-nine thousand, six hundred twenty-one".