1961669815680 has 64 divisors (see below), whose sum is σ = 6252822543600. Its totient is φ = 523111950336.

The previous prime is 1961669815661. The next prime is 1961669815681. The reversal of 1961669815680 is 865189661691.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1961669815681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 510849595 + ... + 510853434.

Almost surely, 2^{1961669815680} is an apocalyptic number.

1961669815680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1961669815680 is an abundant number, since it is smaller than the sum of its proper divisors (4291152727920).

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

1961669815680 is a wasteful number, since it uses less digits than its factorization.

1961669815680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1021703051 (or 1021703039 counting only the distinct ones).

The product of its (nonzero) digits is 33592320, while the sum is 66.

The spelling of 1961669815680 in words is "one trillion, nine hundred sixty-one billion, six hundred sixty-nine million, eight hundred fifteen thousand, six hundred eighty".