12688740 has 72 divisors (see below), whose sum is σ = 38820600. Its totient is φ = 3354624.

The previous prime is 12688733. The next prime is 12688757. The reversal of 12688740 is 4788621.

It can be written as a sum of positive squares in 4 ways, for example, as 910116 + 11778624 = 954^2 + 3432^2 .

It is a super-2 number, since 2×12688740² = 322008245575200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 12688695 and 12688704.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 28036 + ... + 28484.

It is an arithmetic number, because the mean of its divisors is an integer number (539175).

Almost surely, 2^12688740 is an apocalyptic number.

12688740 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 12688740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19410300).

12688740 is an abundant number, since it is smaller than the sum of its proper divisors (26131860).

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

12688740 is a wasteful number, since it uses less digits than its factorization.

12688740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 621 (or 616 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 12688740 is about 3562.1257698178. The cubic root of 12688740 is about 233.2416828264.

The spelling of 12688740 in words is "twelve million, six hundred eighty-eight thousand, seven hundred forty".