829087821 has 6 divisors (see below), whose sum is σ = 1197571310. Its totient is φ = 552725208.

The previous prime is 829087817. The next prime is 829087843. The reversal of 829087821 is 128780928.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 801682596 + 27405225 = 28314^2 + 5235^2 .

It is not a de Polignac number, because 829087821 - 2² = 829087817 is a prime.

It is a super-2 number, since 2×829087821² = 1374773229861056082, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (829087871) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 46060426 + ... + 46060443.

Almost surely, 2^829087821 is an apocalyptic number.

It is an amenable number.

829087821 is a deficient number, since it is larger than the sum of its proper divisors (368483489).

829087821 is a wasteful number, since it uses less digits than its factorization.

829087821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92120875 (or 92120872 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The square root of 829087821 is about 28793.8851320901. The cubic root of 829087821 is about 939.4352352932.

The spelling of 829087821 in words is "eight hundred twenty-nine million, eighty-seven thousand, eight hundred twenty-one".