21471217413 has 16 divisors (see below), whose sum is σ = 30543708096. Its totient is φ = 13369291520.

The previous prime is 21471217357. The next prime is 21471217421. The reversal of 21471217413 is 31471217412.

It is a cyclic number.

It is not a de Polignac number, because 21471217413 - 2⁹ = 21471216901 is a prime.

It is a super-2 number, since 2×21471217413² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21471217513) 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 15 ways as a sum of consecutive naturals, for example, 1600206 + ... + 1613567.

It is an arithmetic number, because the mean of its divisors is an integer number (1908981756).

Almost surely, 2^21471217413 is an apocalyptic number.

It is an amenable number.

21471217413 is a deficient number, since it is larger than the sum of its proper divisors (9072490683).

21471217413 is a wasteful number, since it uses less digits than its factorization.

21471217413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3213924.

The product of its digits is 9408, while the sum is 33.

Subtracting 21471217413 from its reverse (31471217412), we obtain a palindrome (9999999999).

The spelling of 21471217413 in words is "twenty-one billion, four hundred seventy-one million, two hundred seventeen thousand, four hundred thirteen".