21112002440 has 32 divisors (see below), whose sum is σ = 47922387480. Its totient is φ = 8370066432.

The previous prime is 21112002419. The next prime is 21112002451. The reversal of 21112002440 is 4420021112.

It can be written as a sum of positive squares in 4 ways, for example, as 5428447684 + 15683554756 = 73678^2 + 125234^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2330879 + ... + 2339918.

Almost surely, 2^21112002440 is an apocalyptic number.

21112002440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21112002440 is an abundant number, since it is smaller than the sum of its proper divisors (26810385040).

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

21112002440 is a wasteful number, since it uses less digits than its factorization.

21112002440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4670921 (or 4670917 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21112002440 its reverse (4420021112), we get a palindrome (25532023552).

The spelling of 21112002440 in words is "twenty-one billion, one hundred twelve million, two thousand, four hundred forty".