73009661 has 2 divisors, whose sum is σ = 73009662. Its totient is φ = 73009660.

The previous prime is 73009649. The next prime is 73009691. The reversal of 73009661 is 16690037.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68989636 + 4020025 = 8306^2 + 2005^2 .

It is a cyclic number.

It is not a de Polignac number, because 73009661 - 2⁶ = 73009597 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (73009691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36504830 + 36504831.

It is an arithmetic number, because the mean of its divisors is an integer number (36504831).

Almost surely, 2^73009661 is an apocalyptic number.

It is an amenable number.

73009661 is a deficient number, since it is larger than the sum of its proper divisors (1).

73009661 is an equidigital number, since it uses as much as digits as its factorization.

73009661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6804, while the sum is 32.

The square root of 73009661 is about 8544.5690938748. The cubic root of 73009661 is about 417.9523556267.

Adding to 73009661 its reverse (16690037), we get a palindrome (89699698).

It can be divided in two parts, 7300 and 9661, that added together give a palindrome (16961).

The spelling of 73009661 in words is "seventy-three million, nine thousand, six hundred sixty-one".