67009661 has 2 divisors, whose sum is σ = 67009662. Its totient is φ = 67009660.

The previous prime is 67009651. The next prime is 67009667. The reversal of 67009661 is 16690076.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59197636 + 7812025 = 7694^2 + 2795^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-67009661 is a prime.

It is equal to p_3952295 and since 67009661 and 3952295 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (67009667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33504830 + 33504831.

It is an arithmetic number, because the mean of its divisors is an integer number (33504831).

Almost surely, 2^67009661 is an apocalyptic number.

It is an amenable number.

67009661 is a deficient number, since it is larger than the sum of its proper divisors (1).

67009661 is an equidigital number, since it uses as much as digits as its factorization.

67009661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 67009661 is about 8185.9428901013. The cubic root of 67009661 is about 406.1743308059.

It can be divided in two parts, 6700 and 9661, that added together give a palindrome (16361).

The spelling of 67009661 in words is "sixty-seven million, nine thousand, six hundred sixty-one".