66951617 has 2 divisors, whose sum is σ = 66951618. Its totient is φ = 66951616.

The previous prime is 66951613. The next prime is 66951623. The reversal of 66951617 is 71615966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37834801 + 29116816 = 6151^2 + 5396^2 .

It is a cyclic number.

It is not a de Polignac number, because 66951617 - 2² = 66951613 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66951613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33475808 + 33475809.

It is an arithmetic number, because the mean of its divisors is an integer number (33475809).

Almost surely, 2^66951617 is an apocalyptic number.

It is an amenable number.

66951617 is a deficient number, since it is larger than the sum of its proper divisors (1).

66951617 is an equidigital number, since it uses as much as digits as its factorization.

66951617 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 41.

The square root of 66951617 is about 8182.3967760064. The cubic root of 66951617 is about 406.0570203914.

The spelling of 66951617 in words is "sixty-six million, nine hundred fifty-one thousand, six hundred seventeen".