17901775640401 has 3 divisors (see below), whose sum is σ = 17901779871451. Its totient is φ = 17901771409352.

The previous prime is 17901775640377. The next prime is 17901775640459. The reversal of 17901775640401 is 10404657710971.

The square root of 17901775640401 is 4231049.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 96751480401 + 17805024160000 = 311049^2 + 4219600^2 .

It is not a de Polignac number, because 17901775640401 - 2²³ = 17901767251793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (17901775640491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 2115525 + ... + 6346573.

Almost surely, 2^{17901775640401} is an apocalyptic number.

17901775640401 is the 4231049-th square number.

17901775640401 is the 2115525-th centered octagonal number.

It is an amenable number.

17901775640401 is a deficient number, since it is larger than the sum of its proper divisors (4231050).

17901775640401 is an frugal number, since it uses more digits than its factorization.

17901775640401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8462098 (or 4231049 counting only the distinct ones).

The product of its (nonzero) digits is 1481760, while the sum is 52.

The spelling of 17901775640401 in words is "seventeen trillion, nine hundred one billion, seven hundred seventy-five million, six hundred forty thousand, four hundred one".