11657640 has 64 divisors (see below), whose sum is σ = 36820800. Its totient is φ = 2944512.

The previous prime is 11657629. The next prime is 11657641. The reversal of 11657640 is 4675611.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

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

It is a junction number, because it is equal to n+sod(n) for n = 11657598 and 11657607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11657641) 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, 277 + ... + 4836.

It is an arithmetic number, because the mean of its divisors is an integer number (575325).

Almost surely, 2^11657640 is an apocalyptic number.

11657640 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 11657640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18410400).

11657640 is an abundant number, since it is smaller than the sum of its proper divisors (25163160).

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

11657640 is a wasteful number, since it uses less digits than its factorization.

11657640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5146 (or 5142 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 11657640 is about 3414.3286309317. The cubic root of 11657640 is about 226.7445618476.

The spelling of 11657640 in words is "eleven million, six hundred fifty-seven thousand, six hundred forty".