66334981 has 2 divisors, whose sum is σ = 66334982. Its totient is φ = 66334980.

The previous prime is 66334973. The next prime is 66334991. The reversal of 66334981 is 18943366.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54154881 + 12180100 = 7359^2 + 3490^2 .

It is a cyclic number.

It is not a de Polignac number, because 66334981 - 2³ = 66334973 is a prime.

It is a super-2 number, since 2×66334981² = 8800659408540722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66334991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33167490 + 33167491.

It is an arithmetic number, because the mean of its divisors is an integer number (33167491).

Almost surely, 2^66334981 is an apocalyptic number.

It is an amenable number.

66334981 is a deficient number, since it is larger than the sum of its proper divisors (1).

66334981 is an equidigital number, since it uses as much as digits as its factorization.

66334981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 93312, while the sum is 40.

The square root of 66334981 is about 8144.6289663802. The cubic root of 66334981 is about 404.8065549779.

The spelling of 66334981 in words is "sixty-six million, three hundred thirty-four thousand, nine hundred eighty-one".