1025640 has 192 divisors, whose sum is σ = 4268160. Its totient is φ = 207360.

The previous prime is 1025623. The next prime is 1025641. The reversal of 1025640 is 465201.

Added to its reverse (465201) it gives a square (1490841 = 1221²).

It is a happy number.

1025640 is a `hidden beast` number, since 1 + 0 + 25 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a zygodrome in base 6.

It is not an unprimeable number, because it can be changed into a prime (1025641) 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 47 ways as a sum of consecutive naturals, for example, 27702 + ... + 27738.

It is an arithmetic number, because the mean of its divisors is an integer number (22230).

2^1025640 is an apocalyptic number.

1025640 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 1025640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2134080).

1025640 is an abundant number, since it is smaller than the sum of its proper divisors (3242520).

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

1025640 is a wasteful number, since it uses less digits than its factorization.

1025640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 1025640 is about 1012.7388607139. The cubic root of 1025640 is about 100.8474644191.

Adding to 1025640 its reverse (465201), we get a square (1490841 = 1221²).

It can be divided in two parts, 10256 and 40, that added together give a triangular number (10296 = T₁₄₃).

The spelling of 1025640 in words is "one million, twenty-five thousand, six hundred forty".