1720990991412 has 144 divisors (see below), whose sum is σ = 5424738988032. Its totient is φ = 446927423040.

The previous prime is 1720990991411. The next prime is 1720990991413. The reversal of 1720990991412 is 2141990990271.

1720990991412 is a `hidden beast` number, since 17 + 209 + 9 + 0 + 9 + 9 + 1 + 412 = 666.

It is an interprime number because it is at equal distance from previous prime (1720990991411) and next prime (1720990991413).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1720990991411) 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, 15598513 + ... + 15708455.

It is an arithmetic number, because the mean of its divisors is an integer number (37671798528).

Almost surely, 2^{1720990991412} is an apocalyptic number.

1720990991412 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 1720990991412, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2712369494016).

1720990991412 is an abundant number, since it is smaller than the sum of its proper divisors (3703747996620).

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

1720990991412 is a wasteful number, since it uses less digits than its factorization.

1720990991412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115618 (or 115613 counting only the distinct ones).

The product of its (nonzero) digits is 734832, while the sum is 54.

The spelling of 1720990991412 in words is "one trillion, seven hundred twenty billion, nine hundred ninety million, nine hundred ninety-one thousand, four hundred twelve".