72720541 has 2 divisors, whose sum is σ = 72720542. Its totient is φ = 72720540.

The previous prime is 72720497. The next prime is 72720547. The reversal of 72720541 is 14502727.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71825625 + 894916 = 8475^2 + 946^2 .

It is an emirp because it is prime and its reverse (14502727) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72720541 - 2⁷ = 72720413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72720547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36360270 + 36360271.

It is an arithmetic number, because the mean of its divisors is an integer number (36360271).

Almost surely, 2^72720541 is an apocalyptic number.

It is an amenable number.

72720541 is a deficient number, since it is larger than the sum of its proper divisors (1).

72720541 is an equidigital number, since it uses as much as digits as its factorization.

72720541 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3920, while the sum is 28.

The square root of 72720541 is about 8527.6339625948. The cubic root of 72720541 is about 417.3999253370.

The spelling of 72720541 in words is "seventy-two million, seven hundred twenty thousand, five hundred forty-one".