290640 has 80 divisors (see below), whose sum is σ = 1035648. Its totient is φ = 66048.

The previous prime is 290627. The next prime is 290657. The reversal of 290640 is 46092.

290640 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

290640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1594 + ... + 1766.

2²⁹⁰⁶⁴⁰ is an apocalyptic number.

290640 is a gapful number since it is divisible by the number (20) 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 290640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (517824).

290640 is an abundant number, since it is smaller than the sum of its proper divisors (745008).

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

290640 is a wasteful number, since it uses less digits than its factorization.

290640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196 (or 190 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 290640 is about 539.1103783086. The cubic root of 290640 is about 66.2397159782.

The spelling of 290640 in words is "two hundred ninety thousand, six hundred forty".