16612681 has 2 divisors, whose sum is σ = 16612682. Its totient is φ = 16612680.

The previous prime is 16612649. The next prime is 16612697. The reversal of 16612681 is 18621661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16605625 + 7056 = 4075^2 + 84^2 .

It is an emirp because it is prime and its reverse (18621661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16612681 - 2⁵ = 16612649 is a prime.

It is a super-2 number, since 2×16612681² = 551962340015522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16612081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8306340 + 8306341.

It is an arithmetic number, because the mean of its divisors is an integer number (8306341).

Almost surely, 2^16612681 is an apocalyptic number.

It is an amenable number.

16612681 is a deficient number, since it is larger than the sum of its proper divisors (1).

16612681 is an equidigital number, since it uses as much as digits as its factorization.

16612681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 31.

The square root of 16612681 is about 4075.8656749211. The cubic root of 16612681 is about 255.1603809740.

The spelling of 16612681 in words is "sixteen million, six hundred twelve thousand, six hundred eighty-one".