1720866920 has 32 divisors (see below), whose sum is σ = 3888172800. Its totient is φ = 685462848.

The previous prime is 1720866919. The next prime is 1720866941. The reversal of 1720866920 is 296680271.

It is a super-2 number, since 2×1720866920² = 5922765912700572800, which contains 22 as substring.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80444 + ... + 99563.

It is an arithmetic number, because the mean of its divisors is an integer number (121505400).

Almost surely, 2^1720866920 is an apocalyptic number.

1720866920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1720866920 is an abundant number, since it is smaller than the sum of its proper divisors (2167305880).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1720866920 is a wasteful number, since it uses less digits than its factorization.

1720866920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180257 (or 180253 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 41.

The square root of 1720866920 is about 41483.3330387036. Note that the first 3 decimals coincide. The cubic root of 1720866920 is about 1198.3465468644.

The spelling of 1720866920 in words is "one billion, seven hundred twenty million, eight hundred sixty-six thousand, nine hundred twenty".