822639640 has 32 divisors (see below), whose sum is σ = 1874376000. Its totient is φ = 324889344.

The previous prime is 822639613. The next prime is 822639691. The reversal of 822639640 is 46936228.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 822639593 and 822639602.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127005 + ... + 133324.

It is an arithmetic number, because the mean of its divisors is an integer number (58574250).

Almost surely, 2^822639640 is an apocalyptic number.

It is an amenable number.

822639640 is an abundant number, since it is smaller than the sum of its proper divisors (1051736360).

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

822639640 is a wasteful number, since it uses less digits than its factorization.

822639640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260419 (or 260415 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 40.

The square root of 822639640 is about 28681.6952079196. The cubic root of 822639640 is about 936.9934268289.

The spelling of 822639640 in words is "eight hundred twenty-two million, six hundred thirty-nine thousand, six hundred forty".