72603281 has 2 divisors, whose sum is σ = 72603282. Its totient is φ = 72603280.

The previous prime is 72603253. The next prime is 72603283. The reversal of 72603281 is 18230627.

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., 50183056 + 22420225 = 7084^2 + 4735^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72603281 is a prime.

It is a super-2 number, since 2×72603281² = 10542472823929922, which contains 22 as substring.

Together with 72603283, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (72603283) 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, 36301640 + 36301641.

It is an arithmetic number, because the mean of its divisors is an integer number (36301641).

Almost surely, 2^72603281 is an apocalyptic number.

It is an amenable number.

72603281 is a deficient number, since it is larger than the sum of its proper divisors (1).

72603281 is an equidigital number, since it uses as much as digits as its factorization.

72603281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 72603281 is about 8520.7558936986. The cubic root of 72603281 is about 417.1754557657.

The spelling of 72603281 in words is "seventy-two million, six hundred three thousand, two hundred eighty-one".