72042517 has 2 divisors, whose sum is σ = 72042518. Its totient is φ = 72042516.

The previous prime is 72042511. The next prime is 72042521. The reversal of 72042517 is 71524027.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48916036 + 23126481 = 6994^2 + 4809^2 .

It is an emirp because it is prime and its reverse (71524027) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72042517 - 2⁷ = 72042389 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72042511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36021258 + 36021259.

It is an arithmetic number, because the mean of its divisors is an integer number (36021259).

Almost surely, 2^72042517 is an apocalyptic number.

It is an amenable number.

72042517 is a deficient number, since it is larger than the sum of its proper divisors (1).

72042517 is an equidigital number, since it uses as much as digits as its factorization.

72042517 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 72042517 is about 8487.7863427398. The cubic root of 72042517 is about 416.0986363895.

The spelling of 72042517 in words is "seventy-two million, forty-two thousand, five hundred seventeen".