72026821 has 2 divisors, whose sum is σ = 72026822. Its totient is φ = 72026820.

The previous prime is 72026789. The next prime is 72026839. The reversal of 72026821 is 12862027.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53450721 + 18576100 = 7311^2 + 4310^2 .

It is a cyclic number.

It is not a de Polignac number, because 72026821 - 2⁵ = 72026789 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 72026821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72026861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36013410 + 36013411.

It is an arithmetic number, because the mean of its divisors is an integer number (36013411).

Almost surely, 2^72026821 is an apocalyptic number.

It is an amenable number.

72026821 is a deficient number, since it is larger than the sum of its proper divisors (1).

72026821 is an equidigital number, since it uses as much as digits as its factorization.

72026821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 72026821 is about 8486.8616696633. The cubic root of 72026821 is about 416.0684155383.

Adding to 72026821 its reverse (12862027), we get a palindrome (84888848).

The spelling of 72026821 in words is "seventy-two million, twenty-six thousand, eight hundred twenty-one".