821361946400 has 36 divisors (see below), whose sum is σ = 2005149853602. Its totient is φ = 328544778240.

The previous prime is 821361946313. The next prime is 821361946469. The reversal of 821361946400 is 4649163128.

It can be written as a sum of positive squares in 3 ways, for example, as 691245913744 + 130116032656 = 831412^2 + 360716^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 513350417 + ... + 513352016.

Almost surely, 2^821361946400 is an apocalyptic number.

821361946400 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

821361946400 is an abundant number, since it is smaller than the sum of its proper divisors (1183787907202).

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

821361946400 is a wasteful number, since it uses less digits than its factorization.

821361946400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1026702453 (or 1026702440 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 44.

The spelling of 821361946400 in words is "eight hundred twenty-one billion, three hundred sixty-one million, nine hundred forty-six thousand, four hundred".