19961765712 has 240 divisors, whose sum is σ = 69697205760. Its totient is φ = 5403044736.

The previous prime is 19961765701. The next prime is 19961765713. The reversal of 19961765712 is 21756716991.

19961765712 is a `hidden beast` number, since 1 + 9 + 9 + 61 + 7 + 6 + 571 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19961765713) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 497803 + ... + 536405.

It is an arithmetic number, because the mean of its divisors is an integer number (290405024).

Almost surely, 2^19961765712 is an apocalyptic number.

19961765712 is a gapful number since it is divisible by the number (12) 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 19961765712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34848602880).

19961765712 is an abundant number, since it is smaller than the sum of its proper divisors (49735440048).

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

19961765712 is a wasteful number, since it uses less digits than its factorization.

19961765712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38652 (or 38634 counting only the distinct ones).

The product of its digits is 1428840, while the sum is 54.

The spelling of 19961765712 in words is "nineteen billion, nine hundred sixty-one million, seven hundred sixty-five thousand, seven hundred twelve".