21519173415 has 16 divisors (see below), whose sum is σ = 34433998848. Its totient is φ = 11475785376.

The previous prime is 21519173341. The next prime is 21519173437. The reversal of 21519173415 is 51437191512.

It is not a de Polignac number, because 21519173415 - 2⁷ = 21519173287 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 105754 + ... + 232856.

It is an arithmetic number, because the mean of its divisors is an integer number (2152124928).

Almost surely, 2^21519173415 is an apocalyptic number.

21519173415 is a deficient number, since it is larger than the sum of its proper divisors (12914825433).

21519173415 is a wasteful number, since it uses less digits than its factorization.

21519173415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138398.

The product of its digits is 37800, while the sum is 39.

The spelling of 21519173415 in words is "twenty-one billion, five hundred nineteen million, one hundred seventy-three thousand, four hundred fifteen".