821852172 has 18 divisors (see below), whose sum is σ = 2077459748. Its totient is φ = 273950712.

The previous prime is 821852167. The next prime is 821852183. The reversal of 821852172 is 271258128.

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-3 number, since 3×821852172³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 22829227 = 821852172 / (8 + 2 + 1 + 8 + 5 + 2 + 1 + 7 + 2).

It is a zygodrome in base 2.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11414578 + ... + 11414649.

Almost surely, 2^821852172 is an apocalyptic number.

It is an amenable number.

821852172 is an abundant number, since it is smaller than the sum of its proper divisors (1255607576).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

821852172 is a wasteful number, since it uses less digits than its factorization.

821852172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22829237 (or 22829232 counting only the distinct ones).

The product of its digits is 17920, while the sum is 36.

The square root of 821852172 is about 28667.9642109446. The cubic root of 821852172 is about 936.6943538349.

The spelling of 821852172 in words is "eight hundred twenty-one million, eight hundred fifty-two thousand, one hundred seventy-two".