21470340243 has 32 divisors (see below), whose sum is σ = 31665369600. Its totient is φ = 12831920640.

The previous prime is 21470340223. The next prime is 21470340253. The reversal of 21470340243 is 34204307412.

It is not a de Polignac number, because 21470340243 - 2²⁹ = 20933469331 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21470340243.

It is not an unprimeable number, because it can be changed into a prime (21470340223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 727605 + ... + 756537.

It is an arithmetic number, because the mean of its divisors is an integer number (989542800).

Almost surely, 2^21470340243 is an apocalyptic number.

21470340243 is a deficient number, since it is larger than the sum of its proper divisors (10195029357).

21470340243 is a wasteful number, since it uses less digits than its factorization.

21470340243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29259.

The product of its (nonzero) digits is 16128, while the sum is 30.

Adding to 21470340243 its reverse (34204307412), we get a palindrome (55674647655).

The spelling of 21470340243 in words is "twenty-one billion, four hundred seventy million, three hundred forty thousand, two hundred forty-three".