72885521 has 2 divisors, whose sum is σ = 72885522. Its totient is φ = 72885520.

The previous prime is 72885517. The next prime is 72885583. The reversal of 72885521 is 12558827.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37945600 + 34939921 = 6160^2 + 5911^2 .

It is a cyclic number.

It is not a de Polignac number, because 72885521 - 2² = 72885517 is a prime.

It is equal to p_4277729 and since 72885521 and 4277729 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (72884521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36442760 + 36442761.

It is an arithmetic number, because the mean of its divisors is an integer number (36442761).

Almost surely, 2^72885521 is an apocalyptic number.

It is an amenable number.

72885521 is a deficient number, since it is larger than the sum of its proper divisors (1).

72885521 is an equidigital number, since it uses as much as digits as its factorization.

72885521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 44800, while the sum is 38.

The square root of 72885521 is about 8537.3017400113. The cubic root of 72885521 is about 417.7153365829.

The spelling of 72885521 in words is "seventy-two million, eight hundred eighty-five thousand, five hundred twenty-one".