1720865993 has 24 divisors (see below), whose sum is σ = 2172219840. Its totient is φ = 1334440800.

The previous prime is 1720865963. The next prime is 1720865999. The reversal of 1720865993 is 3995680271.

It is not a de Polignac number, because 1720865993 - 2⁸ = 1720865737 is a prime.

It is a super-2 number, since 2×1720865993² = 5922759531727752098, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1720865999) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 173903 + ... + 183531.

It is an arithmetic number, because the mean of its divisors is an integer number (90509160).

Almost surely, 2^1720865993 is an apocalyptic number.

It is an amenable number.

1720865993 is a deficient number, since it is larger than the sum of its proper divisors (451353847).

1720865993 is a wasteful number, since it uses less digits than its factorization.

1720865993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9869 (or 9858 counting only the distinct ones).

The product of its (nonzero) digits is 816480, while the sum is 50.

The square root of 1720865993 is about 41483.3218655401. The cubic root of 1720865993 is about 1198.3463316885.

The spelling of 1720865993 in words is "one billion, seven hundred twenty million, eight hundred sixty-five thousand, nine hundred ninety-three".