12215840 has 96 divisors (see below), whose sum is σ = 35562240. Its totient is φ = 3861504.

The previous prime is 12215831. The next prime is 12215851. The reversal of 12215840 is 4851221.

12215840 is nontrivially palindromic in base 3.

It is a nialpdrome in base 16.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14141 + ... + 14979.

It is an arithmetic number, because the mean of its divisors is an integer number (370440).

Almost surely, 2^12215840 is an apocalyptic number.

12215840 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 12215840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17781120).

12215840 is an abundant number, since it is smaller than the sum of its proper divisors (23346400).

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

12215840 is a wasteful number, since it uses less digits than its factorization.

12215840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 874 (or 866 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 12215840 is about 3495.1165931911. The cubic root of 12215840 is about 230.3073396043.

The spelling of 12215840 in words is "twelve million, two hundred fifteen thousand, eight hundred forty".