821428642940 has 12 divisors (see below), whose sum is σ = 1725000150216. Its totient is φ = 328571457168.

The previous prime is 821428642919. The next prime is 821428642981. The reversal of 821428642940 is 49246824128.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20535716054 + ... + 20535716093.

It is an arithmetic number, because the mean of its divisors is an integer number (143750012518).

Almost surely, 2^821428642940 is an apocalyptic number.

It is an amenable number.

821428642940 is an abundant number, since it is smaller than the sum of its proper divisors (903571507276).

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

821428642940 is a wasteful number, since it uses less digits than its factorization.

821428642940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41071432156 (or 41071432154 counting only the distinct ones).

The product of its (nonzero) digits is 1769472, while the sum is 50.

The spelling of 821428642940 in words is "eight hundred twenty-one billion, four hundred twenty-eight million, six hundred forty-two thousand, nine hundred forty".