73706221 has 2 divisors, whose sum is σ = 73706222. Its totient is φ = 73706220.

The previous prime is 73706207. The next prime is 73706249. The reversal of 73706221 is 12260737.

It is an a-pointer prime, because the next prime (73706249) can be obtained adding 73706221 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38303721 + 35402500 = 6189^2 + 5950^2 .

It is a cyclic number.

It is not a de Polignac number, because 73706221 - 2²³ = 65317613 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 73706221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (73706261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36853110 + 36853111.

It is an arithmetic number, because the mean of its divisors is an integer number (36853111).

Almost surely, 2^73706221 is an apocalyptic number.

It is an amenable number.

73706221 is a deficient number, since it is larger than the sum of its proper divisors (1).

73706221 is an equidigital number, since it uses as much as digits as its factorization.

73706221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3528, while the sum is 28.

The square root of 73706221 is about 8585.2327283540. The cubic root of 73706221 is about 419.2773305764.

Adding to 73706221 its reverse (12260737), we get a palindrome (85966958).

The spelling of 73706221 in words is "seventy-three million, seven hundred six thousand, two hundred twenty-one".