21669315938517 has 16 divisors (see below), whose sum is σ = 31124427732608. Its totient is φ = 13330886852160.

The previous prime is 21669315938467. The next prime is 21669315938563. The reversal of 21669315938517 is 71583951396612.

It is not a de Polignac number, because 21669315938517 - 2¹² = 21669315934421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21669315938587) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84804178 + ... + 85059315.

It is an arithmetic number, because the mean of its divisors is an integer number (1945276733288).

Almost surely, 2^{21669315938517} is an apocalyptic number.

It is an amenable number.

21669315938517 is a deficient number, since it is larger than the sum of its proper divisors (9455111794091).

21669315938517 is a wasteful number, since it uses less digits than its factorization.

21669315938517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169866780.

The product of its digits is 73483200, while the sum is 66.

The spelling of 21669315938517 in words is "twenty-one trillion, six hundred sixty-nine billion, three hundred fifteen million, nine hundred thirty-eight thousand, five hundred seventeen".