1977195965520 has 160 divisors (see below), whose sum is σ = 6217220822400. Its totient is φ = 519699013632.

The previous prime is 1977195965509. The next prime is 1977195965551. The reversal of 1977195965520 is 255695917791.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28154611 + ... + 28224749.

It is an arithmetic number, because the mean of its divisors is an integer number (38857630140).

Almost surely, 2^{1977195965520} is an apocalyptic number.

1977195965520 is a gapful number since it is divisible by the number (10) 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 1977195965520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3108610411200).

1977195965520 is an abundant number, since it is smaller than the sum of its proper divisors (4240024856880).

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

1977195965520 is a wasteful number, since it uses less digits than its factorization.

1977195965520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71837 (or 71831 counting only the distinct ones).

The product of its (nonzero) digits is 53581500, while the sum is 66.

The spelling of 1977195965520 in words is "one trillion, nine hundred seventy-seven billion, one hundred ninety-five million, nine hundred sixty-five thousand, five hundred twenty".