72211217 has 8 divisors (see below), whose sum is σ = 78198120. Its totient is φ = 66286080.

The previous prime is 72211213. The next prime is 72211219. The reversal of 72211217 is 71211227.

It can be written as a sum of positive squares in 4 ways, for example, as 2972176 + 69239041 = 1724^2 + 8321^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 72211217 - 2² = 72211213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 72211192 and 72211201.

It is not an unprimeable number, because it can be changed into a prime (72211213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12992 + ... + 17697.

It is an arithmetic number, because the mean of its divisors is an integer number (9774765).

Almost surely, 2^72211217 is an apocalyptic number.

It is an amenable number.

72211217 is a deficient number, since it is larger than the sum of its proper divisors (5986903).

72211217 is a wasteful number, since it uses less digits than its factorization.

72211217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30883.

The product of its digits is 392, while the sum is 23.

The square root of 72211217 is about 8497.7183408254. The cubic root of 72211217 is about 416.4231721505.

The spelling of 72211217 in words is "seventy-two million, two hundred eleven thousand, two hundred seventeen".