72856643 has 2 divisors, whose sum is σ = 72856644. Its totient is φ = 72856642.

The previous prime is 72856607. The next prime is 72856657. The reversal of 72856643 is 34665827.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 72856643 - 2¹⁴ = 72840259 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72856643.

It is not a weakly prime, because it can be changed into another prime (72852643) 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, 36428321 + 36428322.

It is an arithmetic number, because the mean of its divisors is an integer number (36428322).

Almost surely, 2^72856643 is an apocalyptic number.

72856643 is a deficient number, since it is larger than the sum of its proper divisors (1).

72856643 is an equidigital number, since it uses as much as digits as its factorization.

72856643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 241920, while the sum is 41.

The square root of 72856643 is about 8535.6102886671. The cubic root of 72856643 is about 417.6601615779.

The spelling of 72856643 in words is "seventy-two million, eight hundred fifty-six thousand, six hundred forty-three".