21041639519 has 4 divisors (see below), whose sum is σ = 21170729496. Its totient is φ = 20912549544.

The previous prime is 21041639513. The next prime is 21041639537. The reversal of 21041639519 is 91593614012.

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 21041639519 - 2⁴ = 21041639503 is a prime.

It is a super-2 number, since 2×21041639519² (a number of 21 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 (21041639513) 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, 64544744 + ... + 64545069.

It is an arithmetic number, because the mean of its divisors is an integer number (5292682374).

Almost surely, 2^21041639519 is an apocalyptic number.

21041639519 is a deficient number, since it is larger than the sum of its proper divisors (129089977).

21041639519 is a wasteful number, since it uses less digits than its factorization.

21041639519 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129089976.

The product of its (nonzero) digits is 58320, while the sum is 41.

The spelling of 21041639519 in words is "twenty-one billion, forty-one million, six hundred thirty-nine thousand, five hundred nineteen".