17920820423401 has 27 divisors (see below), whose sum is σ = 20914486109181. Its totient is φ = 15310894224024.

The previous prime is 17920820423371. The next prime is 17920820423477. The reversal of 17920820423401 is 10432402802971.

The square root of 17920820423401 is 4233299.

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

It is not a de Polignac number, because 17920820423401 - 2¹¹ = 17920820421353 is a prime.

It is a hoax number, since the sum of its digits (43) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (17920820423101) by changing a digit.

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 26 ways as a sum of consecutive naturals, for example, 11349473830 + ... + 11349475408.

Almost surely, 2^{17920820423401} is an apocalyptic number.

17920820423401 is the 4233299-th square number.

17920820423401 is the 2116650-th centered octagonal number.

It is an amenable number.

17920820423401 is a deficient number, since it is larger than the sum of its proper divisors (2993665685780).

17920820423401 is an frugal number, since it uses more digits than its factorization.

17920820423401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3938 (or 1969 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 43.

The spelling of 17920820423401 in words is "seventeen trillion, nine hundred twenty billion, eight hundred twenty million, four hundred twenty-three thousand, four hundred one".