21517216215414 has 8 divisors (see below), whose sum is σ = 43034432430840. Its totient is φ = 7172405405136.

The previous prime is 21517216215403. The next prime is 21517216215461. The reversal of 21517216215414 is 41451261271512.

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

21517216215414 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1793101351279 + ... + 1793101351290.

It is an arithmetic number, because the mean of its divisors is an integer number (5379304053855).

Almost surely, 2^{21517216215414} is an apocalyptic number.

21517216215414 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21517216215414 is a wasteful number, since it uses less digits than its factorization.

21517216215414 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3586202702574.

The product of its digits is 134400, while the sum is 42.

Adding to 21517216215414 its reverse (41451261271512), we get a palindrome (62968477486926).

The spelling of 21517216215414 in words is "twenty-one trillion, five hundred seventeen billion, two hundred sixteen million, two hundred fifteen thousand, four hundred fourteen".