21344400040 has 16 divisors (see below), whose sum is σ = 48024900180. Its totient is φ = 8537760000.

The previous prime is 21344400013. The next prime is 21344400061. The reversal of 21344400040 is 4000444312.

It can be written as a sum of positive squares in 2 ways, for example, as 19210514404 + 2133885636 = 138602^2 + 46194^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21344399984 and 21344400020.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 266804961 + ... + 266805040.

Almost surely, 2^21344400040 is an apocalyptic number.

21344400040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21344400040 is an abundant number, since it is smaller than the sum of its proper divisors (26680500140).

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

21344400040 is a wasteful number, since it uses less digits than its factorization.

21344400040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 533610012 (or 533610008 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 22.

Adding to 21344400040 its reverse (4000444312), we get a palindrome (25344844352).

It can be divided in two parts, 213444000 and 40, that multiplied together give a square (8537760000 = 92400²).

The spelling of 21344400040 in words is "twenty-one billion, three hundred forty-four million, four hundred thousand, forty".