783640 has 64 divisors (see below), whose sum is σ = 2086560. Its totient is φ = 261120.

The previous prime is 783619. The next prime is 783641. The reversal of 783640 is 46387.

It is a super-2 number, since 2×783640² = 1228183299200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 783599 and 783608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (783641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5652 + ... + 5788.

2⁷⁸³⁶⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 783640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1043280).

783640 is an abundant number, since it is smaller than the sum of its proper divisors (1302920).

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

783640 is a wasteful number, since it uses less digits than its factorization.

783640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172 (or 168 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 783640 is about 885.2344322269. The cubic root of 783640 is about 92.1946100999.

The spelling of 783640 in words is "seven hundred eighty-three thousand, six hundred forty".