699840 has 112 divisors (see below), whose sum is σ = 2499360. Its totient is φ = 186624.

The previous prime is 699823. The next prime is 699863. The reversal of 699840 is 48996.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 699795 and 699804.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 699840.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139966 + ... + 139970.

699840 is a Friedman number, since it can be written as 8640*9*9, using all its digits and the basic arithmetic operations.

2⁶⁹⁹⁸⁴⁰ is an apocalyptic number.

699840 is a gapful number since it is divisible by the number (60) 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 699840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1249680).

699840 is an abundant number, since it is smaller than the sum of its proper divisors (1799520).

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

699840 is an frugal number, since it uses more digits than its factorization.

699840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38 (or 10 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 699840 is about 836.5644027808. The cubic root of 699840 is about 88.7836346759.

699840 divided by its product of nonzero digits (15552) gives a triangular number (45 = T₉).

The spelling of 699840 in words is "six hundred ninety-nine thousand, eight hundred forty".