21222040040 has 32 divisors (see below), whose sum is σ = 48013416360. Its totient is φ = 8441913600.

The previous prime is 21222040031. The next prime is 21222040069. The reversal of 21222040040 is 4004022212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 7080549316 + 14141490724 = 84146^2 + 118918^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1458371 + ... + 1472850.

Almost surely, 2^21222040040 is an apocalyptic number.

21222040040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21222040040 is an abundant number, since it is smaller than the sum of its proper divisors (26791376320).

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

21222040040 is a wasteful number, since it uses less digits than its factorization.

21222040040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2931413 (or 2931409 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 17.

Adding to 21222040040 its reverse (4004022212), we get a palindrome (25226062252).

The spelling of 21222040040 in words is "twenty-one billion, two hundred twenty-two million, forty thousand, forty".