72135541 has 2 divisors, whose sum is σ = 72135542. Its totient is φ = 72135540.

The previous prime is 72135493. The next prime is 72135551. The reversal of 72135541 is 14553127.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51696100 + 20439441 = 7190^2 + 4521^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72135541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72135551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36067770 + 36067771.

It is an arithmetic number, because the mean of its divisors is an integer number (36067771).

Almost surely, 2^72135541 is an apocalyptic number.

It is an amenable number.

72135541 is a deficient number, since it is larger than the sum of its proper divisors (1).

72135541 is an equidigital number, since it uses as much as digits as its factorization.

72135541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4200, while the sum is 28.

The square root of 72135541 is about 8493.2644489619. The cubic root of 72135541 is about 416.2776534157.

Adding to 72135541 its reverse (14553127), we get a palindrome (86688668).

The spelling of 72135541 in words is "seventy-two million, one hundred thirty-five thousand, five hundred forty-one".