21130043240 has 64 divisors (see below), whose sum is σ = 50723703360. Its totient is φ = 7894082560.

The previous prime is 21130043239. The next prime is 21130043243. The reversal of 21130043240 is 4234003112.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (21130043243) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29522 + ... + 207681.

It is an arithmetic number, because the mean of its divisors is an integer number (792557865).

Almost surely, 2^21130043240 is an apocalyptic number.

21130043240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21130043240 is an abundant number, since it is smaller than the sum of its proper divisors (29593660120).

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

21130043240 is a wasteful number, since it uses less digits than its factorization.

21130043240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237362 (or 237358 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21130043240 its reverse (4234003112), we get a palindrome (25364046352).

The spelling of 21130043240 in words is "twenty-one billion, one hundred thirty million, forty-three thousand, two hundred forty".