1961821024128 has 384 divisors, whose sum is σ = 7025593536000. Its totient is φ = 512707055616.

The previous prime is 1961821024039. The next prime is 1961821024181. The reversal of 1961821024128 is 8214201281691.

1961821024128 is a `hidden beast` number, since 1 + 9 + 6 + 18 + 210 + 2 + 412 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4222501 + ... + 4664027.

It is an arithmetic number, because the mean of its divisors is an integer number (18295816500).

Almost surely, 2^{1961821024128} is an apocalyptic number.

1961821024128 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1961821024128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3512796768000).

1961821024128 is an abundant number, since it is smaller than the sum of its proper divisors (5063772511872).

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

1961821024128 is a wasteful number, since it uses less digits than its factorization.

1961821024128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441602 (or 441587 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 45.

The spelling of 1961821024128 in words is "one trillion, nine hundred sixty-one billion, eight hundred twenty-one million, twenty-four thousand, one hundred twenty-eight".