1689943920 has 320 divisors, whose sum is σ = 6354640896. Its totient is φ = 363294720.

The previous prime is 1689943907. The next prime is 1689943921. The reversal of 1689943920 is 293499861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1689943921) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1926522 + ... + 1927398.

Almost surely, 2^1689943920 is an apocalyptic number.

1689943920 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 1689943920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3177320448).

1689943920 is an abundant number, since it is smaller than the sum of its proper divisors (4664696976).

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

1689943920 is a wasteful number, since it uses less digits than its factorization.

1689943920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 968 (or 962 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 51.

The square root of 1689943920 is about 41108.9274975643. The cubic root of 1689943920 is about 1191.1252496971.

The spelling of 1689943920 in words is "one billion, six hundred eighty-nine million, nine hundred forty-three thousand, nine hundred twenty".