12640280040 has 160 divisors (see below), whose sum is σ = 42611611680. Its totient is φ = 3360728448.

The previous prime is 12640280021. The next prime is 12640280053. The reversal of 12640280040 is 4008204621.

12640280040 is a `hidden beast` number, since 12 + 640 + 2 + 8 + 0 + 0 + 4 + 0 = 666.

It is a Cunningham number, because it is equal to 112429²-1.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 12640279986 and 12640280013.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1118659 + ... + 1129901.

It is an arithmetic number, because the mean of its divisors is an integer number (266322573).

Almost surely, 2^12640280040 is an apocalyptic number.

12640280040 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 12640280040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21305805840).

12640280040 is an abundant number, since it is smaller than the sum of its proper divisors (29971331640).

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

12640280040 is a wasteful number, since it uses less digits than its factorization.

12640280040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11613 (or 11600 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

Adding to 12640280040 its reverse (4008204621), we get a palindrome (16648484661).

The spelling of 12640280040 in words is "twelve billion, six hundred forty million, two hundred eighty thousand, forty".