72191533 has 2 divisors, whose sum is σ = 72191534. Its totient is φ = 72191532.

The previous prime is 72191521. The next prime is 72191573. The reversal of 72191533 is 33519127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66536649 + 5654884 = 8157^2 + 2378^2 .

It is an emirp because it is prime and its reverse (33519127) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72191533 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 72191495 and 72191504.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72191513) 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 as a sum of consecutive naturals, namely, 36095766 + 36095767.

It is an arithmetic number, because the mean of its divisors is an integer number (36095767).

Almost surely, 2^72191533 is an apocalyptic number.

It is an amenable number.

72191533 is a deficient number, since it is larger than the sum of its proper divisors (1).

72191533 is an equidigital number, since it uses as much as digits as its factorization.

72191533 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5670, while the sum is 31.

The square root of 72191533 is about 8496.5600686395. The cubic root of 72191533 is about 416.3853312214.

The spelling of 72191533 in words is "seventy-two million, one hundred ninety-one thousand, five hundred thirty-three".