21471028299839 has 4 divisors (see below), whose sum is σ = 21471097922640. Its totient is φ = 21470958677040.

The previous prime is 21471028299823. The next prime is 21471028299841. The reversal of 21471028299839 is 93899282017412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21471028299839 - 2⁴ = 21471028299823 is a prime.

It is a super-2 number, since 2×21471028299839² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21471028292839) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34346747 + ... + 34966284.

It is an arithmetic number, because the mean of its divisors is an integer number (5367774480660).

Almost surely, 2^{21471028299839} is an apocalyptic number.

21471028299839 is a deficient number, since it is larger than the sum of its proper divisors (69622801).

21471028299839 is an equidigital number, since it uses as much as digits as its factorization.

21471028299839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69622800.

The product of its (nonzero) digits is 31352832, while the sum is 65.

The spelling of 21471028299839 in words is "twenty-one trillion, four hundred seventy-one billion, twenty-eight million, two hundred ninety-nine thousand, eight hundred thirty-nine".