1989765400770 has 192 divisors, whose sum is σ = 6128508672000. Its totient is φ = 438305126400.

The previous prime is 1989765400699. The next prime is 1989765400789. The reversal of 1989765400770 is 770045679891.

1989765400770 is a `hidden beast` number, since 1 + 9 + 89 + 7 + 6 + 540 + 0 + 7 + 7 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 1989765400698 and 1989765400707.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4495356 + ... + 4918104.

It is an arithmetic number, because the mean of its divisors is an integer number (31919316000).

Almost surely, 2^{1989765400770} is an apocalyptic number.

1989765400770 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1989765400770, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3064254336000).

1989765400770 is an abundant number, since it is smaller than the sum of its proper divisors (4138743271230).

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

1989765400770 is a wasteful number, since it uses less digits than its factorization.

1989765400770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423041 (or 423038 counting only the distinct ones).

The product of its (nonzero) digits is 26671680, while the sum is 63.

The spelling of 1989765400770 in words is "one trillion, nine hundred eighty-nine billion, seven hundred sixty-five million, four hundred thousand, seven hundred seventy".