821312870 has 32 divisors (see below), whose sum is σ = 1690730496. Its totient is φ = 281397600.

The previous prime is 821312839. The next prime is 821312873. The reversal of 821312870 is 78213128.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821312873) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 127835 + ... + 134105.

It is an arithmetic number, because the mean of its divisors is an integer number (52835328).

Almost surely, 2^821312870 is an apocalyptic number.

821312870 is an abundant number, since it is smaller than the sum of its proper divisors (869417626).

821312870 is a wasteful number, since it uses less digits than its factorization.

821312870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8156.

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 821312870 is about 28658.5566628887. The cubic root of 821312870 is about 936.4894217347.

Adding to 821312870 its reverse (78213128), we get a palindrome (899525998).

The spelling of 821312870 in words is "eight hundred twenty-one million, three hundred twelve thousand, eight hundred seventy".