12221405640 has 48 divisors (see below), whose sum is σ = 39719569500. Its totient is φ = 3259041408.

The previous prime is 12221405563. The next prime is 12221405641. The reversal of 12221405640 is 4650412221.

12221405640 is a `hidden beast` number, since 1 + 2 + 2 + 2 + 14 + 0 + 5 + 640 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 11366544996 + 854860644 = 106614^2 + 29238^2 .

It is not an unprimeable number, because it can be changed into a prime (12221405641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16973815 + ... + 16974534.

Almost surely, 2^12221405640 is an apocalyptic number.

12221405640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12221405640 is an abundant number, since it is smaller than the sum of its proper divisors (27498163860).

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

12221405640 is a wasteful number, since it uses less digits than its factorization.

12221405640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33948366 (or 33948359 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

Adding to 12221405640 its reverse (4650412221), we get a palindrome (16871817861).

The spelling of 12221405640 in words is "twelve billion, two hundred twenty-one million, four hundred five thousand, six hundred forty".