1720431705 has 32 divisors (see below), whose sum is σ = 2917085184. Its totient is φ = 862857216.

The previous prime is 1720431683. The next prime is 1720431737. The reversal of 1720431705 is 5071340271.

It is not a de Polignac number, because 1720431705 - 2⁷ = 1720431577 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 422037 + ... + 426093.

It is an arithmetic number, because the mean of its divisors is an integer number (91158912).

Almost surely, 2^1720431705 is an apocalyptic number.

1720431705 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1720431705 is a deficient number, since it is larger than the sum of its proper divisors (1196653479).

1720431705 is a wasteful number, since it uses less digits than its factorization.

1720431705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5745.

The product of its (nonzero) digits is 5880, while the sum is 30.

The square root of 1720431705 is about 41478.0870460536. The cubic root of 1720431705 is about 1198.2455159326.

Adding to 1720431705 its reverse (5071340271), we get a palindrome (6791771976).

The spelling of 1720431705 in words is "one billion, seven hundred twenty million, four hundred thirty-one thousand, seven hundred five".