66953771 has 2 divisors, whose sum is σ = 66953772. Its totient is φ = 66953770.

The previous prime is 66953753. The next prime is 66953773. The reversal of 66953771 is 17735966.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66953771 - 2²² = 62759467 is a prime.

It is a super-2 number, since 2×66953771² = 8965614902240882, which contains 22 as substring.

Together with 66953773, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66953773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33476885 + 33476886.

It is an arithmetic number, because the mean of its divisors is an integer number (33476886).

Almost surely, 2^66953771 is an apocalyptic number.

66953771 is a deficient number, since it is larger than the sum of its proper divisors (1).

66953771 is an equidigital number, since it uses as much as digits as its factorization.

66953771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 238140, while the sum is 44.

The square root of 66953771 is about 8182.5283989730. The cubic root of 66953771 is about 406.0613749660.

The spelling of 66953771 in words is "sixty-six million, nine hundred fifty-three thousand, seven hundred seventy-one".