7865520 has 80 divisors (see below), whose sum is σ = 26269152. Its totient is φ = 1935360.

The previous prime is 7865519. The next prime is 7865527. The reversal of 7865520 is 255687.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (7865527) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1860 + ... + 4380.

Almost surely, 2^7865520 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 7865520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13134576).

7865520 is an abundant number, since it is smaller than the sum of its proper divisors (18403632).

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

7865520 is a wasteful number, since it uses less digits than its factorization.

7865520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2550 (or 2544 counting only the distinct ones).

The product of its (nonzero) digits is 16800, while the sum is 33.

The square root of 7865520 is about 2804.5534403894. The cubic root of 7865520 is about 198.8729945558.

It can be divided in two parts, 7865 and 520, that added together give a triangular number (8385 = T₁₂₉).

The spelling of 7865520 in words is "seven million, eight hundred sixty-five thousand, five hundred twenty".