72888209 has 2 divisors, whose sum is σ = 72888210. Its totient is φ = 72888208.

The previous prime is 72888149. The next prime is 72888239. The reversal of 72888209 is 90288827.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57047809 + 15840400 = 7553^2 + 3980^2 .

It is a cyclic number.

It is not a de Polignac number, because 72888209 - 2²⁰ = 71839633 is a prime.

It is a super-2 number, since 2×72888209² = 10625382022455362, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 72888209.

It is not a weakly prime, because it can be changed into another prime (72888239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36444104 + 36444105.

It is an arithmetic number, because the mean of its divisors is an integer number (36444105).

Almost surely, 2^72888209 is an apocalyptic number.

It is an amenable number.

72888209 is a deficient number, since it is larger than the sum of its proper divisors (1).

72888209 is an equidigital number, since it uses as much as digits as its factorization.

72888209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 129024, while the sum is 44.

The square root of 72888209 is about 8537.4591653489. The cubic root of 72888209 is about 417.7204715993.

The spelling of 72888209 in words is "seventy-two million, eight hundred eighty-eight thousand, two hundred nine".