21130043242 has 16 divisors (see below), whose sum is σ = 39515925312. Its totient is φ = 8232484320.

The previous prime is 21130043239. The next prime is 21130043243. The reversal of 21130043242 is 24234003112.

It is a Harshad number since it is a multiple of its sum of digits (22).

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 7 ways as a sum of consecutive naturals, for example, 68603883 + ... + 68604190.

It is an arithmetic number, because the mean of its divisors is an integer number (2469745332).

Almost surely, 2^21130043242 is an apocalyptic number.

21130043242 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21130043242 is a deficient number, since it is larger than the sum of its proper divisors (18385882070).

21130043242 is a wasteful number, since it uses less digits than its factorization.

21130043242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137208093.

The product of its (nonzero) digits is 1152, while the sum is 22.

Adding to 21130043242 its reverse (24234003112), we get a palindrome (45364046354).

The spelling of 21130043242 in words is "twenty-one billion, one hundred thirty million, forty-three thousand, two hundred forty-two".