8615640 has 128 divisors (see below), whose sum is σ = 28926720. Its totient is φ = 2035200.

The previous prime is 8615623. The next prime is 8615653. The reversal of 8615640 is 465168.

8615640 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 8615598 and 8615607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 80467 + ... + 80573.

It is an arithmetic number, because the mean of its divisors is an integer number (225990).

Almost surely, 2^8615640 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 8615640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14463360).

8615640 is an abundant number, since it is smaller than the sum of its proper divisors (20311080).

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

8615640 is a wasteful number, since it uses less digits than its factorization.

8615640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193 (or 189 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 8615640 is about 2935.2410463197. The cubic root of 8615640 is about 205.0040847887.

The spelling of 8615640 in words is "eight million, six hundred fifteen thousand, six hundred forty".