83216681 has 2 divisors, whose sum is σ = 83216682. Its totient is φ = 83216680.

The previous prime is 83216669. The next prime is 83216699. The reversal of 83216681 is 18661238.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65869456 + 17347225 = 8116^2 + 4165^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-83216681 is a prime.

It is a super-2 number, since 2×83216681² = 13850031993311522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (83216281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41608340 + 41608341.

It is an arithmetic number, because the mean of its divisors is an integer number (41608341).

Almost surely, 2^83216681 is an apocalyptic number.

It is an amenable number.

83216681 is a deficient number, since it is larger than the sum of its proper divisors (1).

83216681 is an equidigital number, since it uses as much as digits as its factorization.

83216681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 35.

The square root of 83216681 is about 9122.3177427669. The cubic root of 83216681 is about 436.5863267952.

The spelling of 83216681 in words is "eighty-three million, two hundred sixteen thousand, six hundred eighty-one".