72690217 has 2 divisors, whose sum is σ = 72690218. Its totient is φ = 72690216.

The previous prime is 72690187. The next prime is 72690227. The reversal of 72690217 is 71209627.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38303721 + 34386496 = 6189^2 + 5864^2 .

It is a cyclic number.

It is not a de Polignac number, because 72690217 - 2¹⁵ = 72657449 is a prime.

It is equal to p_4266907 and since 72690217 and 4266907 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (72690227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36345108 + 36345109.

It is an arithmetic number, because the mean of its divisors is an integer number (36345109).

Almost surely, 2^72690217 is an apocalyptic number.

It is an amenable number.

72690217 is a deficient number, since it is larger than the sum of its proper divisors (1).

72690217 is an equidigital number, since it uses as much as digits as its factorization.

72690217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10584, while the sum is 34.

The square root of 72690217 is about 8525.8557928222. The cubic root of 72690217 is about 417.3418995719.

The spelling of 72690217 in words is "seventy-two million, six hundred ninety thousand, two hundred seventeen".