81624679 has 2 divisors, whose sum is σ = 81624680. Its totient is φ = 81624678.

The previous prime is 81624637. The next prime is 81624691. The reversal of 81624679 is 97642618.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81624679 - 2¹¹ = 81622631 is a prime.

It is equal to p_4758829 and since 81624679 and 4758829 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81624619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40812339 + 40812340.

It is an arithmetic number, because the mean of its divisors is an integer number (40812340).

Almost surely, 2^81624679 is an apocalyptic number.

81624679 is a deficient number, since it is larger than the sum of its proper divisors (1).

81624679 is an equidigital number, since it uses as much as digits as its factorization.

81624679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 43.

The square root of 81624679 is about 9034.6377348514. The cubic root of 81624679 is about 433.7842992917.

The spelling of 81624679 in words is "eighty-one million, six hundred twenty-four thousand, six hundred seventy-nine".