21717370145 has 8 divisors (see below), whose sum is σ = 26076468840. Its totient is φ = 17363479680.

The previous prime is 21717370141. The next prime is 21717370183. The reversal of 21717370145 is 54107371712.

It can be written as a sum of positive squares in 4 ways, for example, as 6622053376 + 15095316769 = 81376^2 + 122863^2 .

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

It is not a de Polignac number, because 21717370145 - 2² = 21717370141 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21717370099 and 21717370108.

It is not an unprimeable number, because it can be changed into a prime (21717370141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1292876 + ... + 1309565.

It is an arithmetic number, because the mean of its divisors is an integer number (3259558605).

Almost surely, 2^21717370145 is an apocalyptic number.

It is an amenable number.

21717370145 is a deficient number, since it is larger than the sum of its proper divisors (4359098695).

21717370145 is a wasteful number, since it uses less digits than its factorization.

21717370145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2604115.

The product of its (nonzero) digits is 41160, while the sum is 38.

The spelling of 21717370145 in words is "twenty-one billion, seven hundred seventeen million, three hundred seventy thousand, one hundred forty-five".