72209537 has 2 divisors, whose sum is σ = 72209538. Its totient is φ = 72209536.

The previous prime is 72209521. The next prime is 72209539. The reversal of 72209537 is 73590227.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46362481 + 25847056 = 6809^2 + 5084^2 .

It is a cyclic number.

It is not a de Polignac number, because 72209537 - 2⁴ = 72209521 is a prime.

Together with 72209539, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 72209497 and 72209506.

It is not a weakly prime, because it can be changed into another prime (72209539) 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, 36104768 + 36104769.

It is an arithmetic number, because the mean of its divisors is an integer number (36104769).

Almost surely, 2^72209537 is an apocalyptic number.

It is an amenable number.

72209537 is a deficient number, since it is larger than the sum of its proper divisors (1).

72209537 is an equidigital number, since it uses as much as digits as its factorization.

72209537 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26460, while the sum is 35.

The square root of 72209537 is about 8497.6194901866. The cubic root of 72209537 is about 416.4199427522.

The spelling of 72209537 in words is "seventy-two million, two hundred nine thousand, five hundred thirty-seven".