12851640 has 96 divisors (see below), whose sum is σ = 43243200. Its totient is φ = 3306240.

The previous prime is 12851621. The next prime is 12851659. The reversal of 12851640 is 4615821.

12851640 is a `hidden beast` number, since 12 + 8 + 5 + 1 + 640 = 666.

It is an interprime number because it is at equal distance from previous prime (12851621) and next prime (12851659).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9825 + ... + 11055.

It is an arithmetic number, because the mean of its divisors is an integer number (450450).

Almost surely, 2^12851640 is an apocalyptic number.

12851640 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 12851640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21621600).

12851640 is an abundant number, since it is smaller than the sum of its proper divisors (30391560).

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

12851640 is a wasteful number, since it uses less digits than its factorization.

12851640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1277 (or 1270 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 12851640 is about 3584.9184091134. The cubic root of 12851640 is about 234.2355725390.

The spelling of 12851640 in words is "twelve million, eight hundred fifty-one thousand, six hundred forty".