1689211720 has 128 divisors (see below), whose sum is σ = 4730400000. Its totient is φ = 529708032.

The previous prime is 1689211709. The next prime is 1689211721. The reversal of 1689211720 is 271129861.

It is a self number, because there is not a number n which added to its sum of digits gives 1689211720.

It is not an unprimeable number, because it can be changed into a prime (1689211721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 148806 + ... + 159754.

It is an arithmetic number, because the mean of its divisors is an integer number (36956250).

Almost surely, 2^1689211720 is an apocalyptic number.

1689211720 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 1689211720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2365200000).

1689211720 is an abundant number, since it is smaller than the sum of its proper divisors (3041188280).

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

1689211720 is a wasteful number, since it uses less digits than its factorization.

1689211720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11015 (or 11011 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 37.

The square root of 1689211720 is about 41100.0209245689. The cubic root of 1689211720 is about 1190.9531990380.

The spelling of 1689211720 in words is "one billion, six hundred eighty-nine million, two hundred eleven thousand, seven hundred twenty".