72533809 has 2 divisors, whose sum is σ = 72533810. Its totient is φ = 72533808.

The previous prime is 72533803. The next prime is 72533827. The reversal of 72533809 is 90833527.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53802225 + 18731584 = 7335^2 + 4328^2 .

It is a cyclic number.

It is not a de Polignac number, because 72533809 - 2⁵ = 72533777 is a prime.

It is a super-2 number, since 2×72533809² = 10522306896096962, which contains 22 as substring.

It is equal to p_4258297 and since 72533809 and 4258297 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 (72533803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36266904 + 36266905.

It is an arithmetic number, because the mean of its divisors is an integer number (36266905).

Almost surely, 2^72533809 is an apocalyptic number.

It is an amenable number.

72533809 is a deficient number, since it is larger than the sum of its proper divisors (1).

72533809 is an equidigital number, since it uses as much as digits as its factorization.

72533809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 37.

The square root of 72533809 is about 8516.6782844017. The cubic root of 72533809 is about 417.0423522208.

The spelling of 72533809 in words is "seventy-two million, five hundred thirty-three thousand, eight hundred nine".