21730043043 has 16 divisors (see below), whose sum is σ = 32554375200. Its totient is φ = 14323921920.

The previous prime is 21730043011. The next prime is 21730043047. The reversal of 21730043043 is 34034003712.

It is not a de Polignac number, because 21730043043 - 2⁵ = 21730043011 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21730042998 and 21730043016.

It is not an unprimeable number, because it can be changed into a prime (21730043047) 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, 4519038 + ... + 4523843.

It is an arithmetic number, because the mean of its divisors is an integer number (2034648450).

Almost surely, 2^21730043043 is an apocalyptic number.

21730043043 is a deficient number, since it is larger than the sum of its proper divisors (10824332157).

21730043043 is an equidigital number, since it uses as much as digits as its factorization.

21730043043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9042979 (or 9042973 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 27.

Adding to 21730043043 its reverse (34034003712), we get a palindrome (55764046755).

The spelling of 21730043043 in words is "twenty-one billion, seven hundred thirty million, forty-three thousand, forty-three".