72821285 has 8 divisors (see below), whose sum is σ = 92525976. Its totient is φ = 54830080.

The previous prime is 72821269. The next prime is 72821297. The reversal of 72821285 is 58212827.

It can be written as a sum of positive squares in 4 ways, for example, as 23512801 + 49308484 = 4849^2 + 7022^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 72821285 - 2⁴ = 72821269 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 428276 + ... + 428445.

It is an arithmetic number, because the mean of its divisors is an integer number (11565747).

Almost surely, 2^72821285 is an apocalyptic number.

It is an amenable number.

72821285 is a deficient number, since it is larger than the sum of its proper divisors (19704691).

72821285 is a wasteful number, since it uses less digits than its factorization.

72821285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 856743.

The product of its digits is 17920, while the sum is 35.

The square root of 72821285 is about 8533.5388321610. The cubic root of 72821285 is about 417.5925858704.

The spelling of 72821285 in words is "seventy-two million, eight hundred twenty-one thousand, two hundred eighty-five".