821506040 has 48 divisors (see below), whose sum is σ = 1950826680. Its totient is φ = 311302080.

The previous prime is 821506039. The next prime is 821506051. The reversal of 821506040 is 40605128.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14006 + ... + 42885.

Almost surely, 2^821506040 is an apocalyptic number.

It is an amenable number.

821506040 is an abundant number, since it is smaller than the sum of its proper divisors (1129320640).

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

821506040 is a wasteful number, since it uses less digits than its factorization.

821506040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56940 (or 56917 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 821506040 is about 28661.9266623861. The cubic root of 821506040 is about 936.5628356908.

The spelling of 821506040 in words is "eight hundred twenty-one million, five hundred six thousand, forty".