21718372215 has 8 divisors (see below), whose sum is σ = 34749395568. Its totient is φ = 11583131840.

The previous prime is 21718372201. The next prime is 21718372241. The reversal of 21718372215 is 51227381712.

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

It is not a de Polignac number, because 21718372215 - 2¹⁹ = 21717847927 is a prime.

It is a congruent number.

It is an unprimeable number.

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, 723945726 + ... + 723945755.

It is an arithmetic number, because the mean of its divisors is an integer number (4343674446).

Almost surely, 2^21718372215 is an apocalyptic number.

21718372215 is a deficient number, since it is larger than the sum of its proper divisors (13031023353).

21718372215 is a wasteful number, since it uses less digits than its factorization.

21718372215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1447891489.

The product of its digits is 47040, while the sum is 39.

The spelling of 21718372215 in words is "twenty-one billion, seven hundred eighteen million, three hundred seventy-two thousand, two hundred fifteen".