21317540919 has 16 divisors (see below), whose sum is σ = 28474368000. Its totient is φ = 14186231136.

The previous prime is 21317540887. The next prime is 21317540921. The reversal of 21317540919 is 91904571312.

It is not a de Polignac number, because 21317540919 - 2⁵ = 21317540887 is a prime.

It is a super-2 number, since 2×21317540919² (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 (21317540929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5123562 + ... + 5127720.

It is an arithmetic number, because the mean of its divisors is an integer number (1779648000).

Almost surely, 2^21317540919 is an apocalyptic number.

21317540919 is a deficient number, since it is larger than the sum of its proper divisors (7156827081).

21317540919 is a wasteful number, since it uses less digits than its factorization.

21317540919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6814.

The product of its (nonzero) digits is 68040, while the sum is 42.

The spelling of 21317540919 in words is "twenty-one billion, three hundred seventeen million, five hundred forty thousand, nine hundred nineteen".