21115430572 has 12 divisors (see below), whose sum is σ = 36953595000. Its totient is φ = 10557260576.

The previous prime is 21115430563. The next prime is 21115430573. The reversal of 21115430572 is 27503451112.

It is a super-2 number, since 2×21115430572² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21115430573) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 4443 + ... + 205549.

It is an arithmetic number, because the mean of its divisors is an integer number (3079466250).

Almost surely, 2^21115430572 is an apocalyptic number.

It is an amenable number.

21115430572 is a deficient number, since it is larger than the sum of its proper divisors (15838164428).

21115430572 is a wasteful number, since it uses less digits than its factorization.

21115430572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227360 (or 227358 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 31.

Adding to 21115430572 its reverse (27503451112), we get a palindrome (48618881684).

The spelling of 21115430572 in words is "twenty-one billion, one hundred fifteen million, four hundred thirty thousand, five hundred seventy-two".