1690880 has 36 divisors (see below), whose sum is σ = 4053252. Its totient is φ = 675840.

The previous prime is 1690853. The next prime is 1690883. The reversal of 1690880 is 880961.

It can be written as a sum of positive squares in 2 ways, for example, as 1149184 + 541696 = 1072^2 + 736^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1690883) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 620 + ... + 1940.

2^1690880 is an apocalyptic number.

1690880 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 1690880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2026626).

1690880 is an abundant number, since it is smaller than the sum of its proper divisors (2362372).

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

1690880 is an equidigital number, since it uses as much as digits as its factorization.

1690880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1342 (or 1328 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 1690880 is about 1300.3384174898. The cubic root of 1690880 is about 119.1345135242.

The spelling of 1690880 in words is "one million, six hundred ninety thousand, eight hundred eighty".