1821421825520 has 40 divisors (see below), whose sum is σ = 4619788086960. Its totient is φ = 662335208960.

The previous prime is 1821421825513. The next prime is 1821421825541. The reversal of 1821421825520 is 255281241281.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1034897885 + ... + 1034899644.

It is an arithmetic number, because the mean of its divisors is an integer number (115494702174).

Almost surely, 2^{1821421825520} is an apocalyptic number.

1821421825520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1821421825520 is an abundant number, since it is smaller than the sum of its proper divisors (2798366261440).

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

1821421825520 is a wasteful number, since it uses less digits than its factorization.

1821421825520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2069797553 (or 2069797547 counting only the distinct ones).

The product of its (nonzero) digits is 102400, while the sum is 41.

The spelling of 1821421825520 in words is "one trillion, eight hundred twenty-one billion, four hundred twenty-one million, eight hundred twenty-five thousand, five hundred twenty".