21691419919 has 8 divisors (see below), whose sum is σ = 23489053952. Its totient is φ = 19912223520.

The previous prime is 21691419917. The next prime is 21691419949. The reversal of 21691419919 is 91991419612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21691419919 - 2¹ = 21691419917 is a prime.

It is a super-2 number, since 2×21691419919² (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 (21691419917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4606959 + ... + 4611664.

It is an arithmetic number, because the mean of its divisors is an integer number (2936131744).

Almost surely, 2^21691419919 is an apocalyptic number.

21691419919 is a deficient number, since it is larger than the sum of its proper divisors (1797634033).

21691419919 is a wasteful number, since it uses less digits than its factorization.

21691419919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9218817.

The product of its digits is 314928, while the sum is 52.

The spelling of 21691419919 in words is "twenty-one billion, six hundred ninety-one million, four hundred nineteen thousand, nine hundred nineteen".