17421657145 has 4 divisors (see below), whose sum is σ = 20905988580. Its totient is φ = 13937325712.

The previous prime is 17421657091. The next prime is 17421657151. The reversal of 17421657145 is 54175612471.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54175612471 = 8219 ⋅6591509.

It can be written as a sum of positive squares in 2 ways, for example, as 2963278096 + 14458379049 = 54436^2 + 120243^2 .

It is a cyclic number.

It is not a de Polignac number, because 17421657145 - 2¹³ = 17421648953 is a prime.

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, 1742165710 + ... + 1742165719.

It is an arithmetic number, because the mean of its divisors is an integer number (5226497145).

Almost surely, 2^17421657145 is an apocalyptic number.

It is an amenable number.

17421657145 is a deficient number, since it is larger than the sum of its proper divisors (3484331435).

17421657145 is an equidigital number, since it uses as much as digits as its factorization.

17421657145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3484331434.

The product of its digits is 235200, while the sum is 43.

It can be divided in two parts, 174216 and 57145, that added together give a square (231361 = 481²).

The spelling of 17421657145 in words is "seventeen billion, four hundred twenty-one million, six hundred fifty-seven thousand, one hundred forty-five".