66834881 has 2 divisors, whose sum is σ = 66834882. Its totient is φ = 66834880.

The previous prime is 66834877. The next prime is 66834899. The reversal of 66834881 is 18843866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43020481 + 23814400 = 6559^2 + 4880^2 .

It is a cyclic number.

It is not a de Polignac number, because 66834881 - 2² = 66834877 is a prime.

It is a super-2 number, since 2×66834881² = 8933802636568322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66831881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33417440 + 33417441.

It is an arithmetic number, because the mean of its divisors is an integer number (33417441).

Almost surely, 2^66834881 is an apocalyptic number.

It is an amenable number.

66834881 is a deficient number, since it is larger than the sum of its proper divisors (1).

66834881 is an equidigital number, since it uses as much as digits as its factorization.

66834881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 221184, while the sum is 44.

The square root of 66834881 is about 8175.2603016662. The cubic root of 66834881 is about 405.8208844537.

The spelling of 66834881 in words is "sixty-six million, eight hundred thirty-four thousand, eight hundred eighty-one".