247282821 has 32 divisors (see below), whose sum is σ = 383523840. Its totient is φ = 157172400.

The previous prime is 247282817. The next prime is 247282829. The reversal of 247282821 is 128282742.

It is not a de Polignac number, because 247282821 - 2² = 247282817 is a prime.

It is a super-2 number, since 2×247282821² = 122297587123436082, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (247282829) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 304506 + ... + 305316.

It is an arithmetic number, because the mean of its divisors is an integer number (11985120).

Almost surely, 2^247282821 is an apocalyptic number.

It is an amenable number.

247282821 is a deficient number, since it is larger than the sum of its proper divisors (136241019).

247282821 is a wasteful number, since it uses less digits than its factorization.

247282821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1334 (or 1328 counting only the distinct ones).

The product of its digits is 28672, while the sum is 36.

The square root of 247282821 is about 15725.2288059665. The cubic root of 247282821 is about 627.6699187994.

The spelling of 247282821 in words is "two hundred forty-seven million, two hundred eighty-two thousand, eight hundred twenty-one".