821402380636 has 24 divisors (see below), whose sum is σ = 1513335321680. Its totient is φ = 389027308032.

The previous prime is 821402380583. The next prime is 821402380637. The reversal of 821402380636 is 636083204128.

It is a junction number, because it is equal to n+sod(n) for n = 821402380592 and 821402380601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821402380637) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 290901 + ... + 1314316.

Almost surely, 2^821402380636 is an apocalyptic number.

It is an amenable number.

821402380636 is a deficient number, since it is larger than the sum of its proper divisors (691932941044).

821402380636 is a wasteful number, since it uses less digits than its factorization.

821402380636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1611973 (or 1611971 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 43.

The spelling of 821402380636 in words is "eight hundred twenty-one billion, four hundred two million, three hundred eighty thousand, six hundred thirty-six".