19965705 has 16 divisors (see below), whose sum is σ = 32976384. Its totient is φ = 10304640.

The previous prime is 19965691. The next prime is 19965709. The reversal of 19965705 is 50756991.

It is not a de Polignac number, because 19965705 - 2⁴ = 19965689 is a prime.

It is a super-3 number, since 3×19965705³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (19965709) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21004 + ... + 21933.

It is an arithmetic number, because the mean of its divisors is an integer number (2061024).

Almost surely, 2^19965705 is an apocalyptic number.

19965705 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19965705 is a deficient number, since it is larger than the sum of its proper divisors (13010679).

19965705 is a wasteful number, since it uses less digits than its factorization.

19965705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42976.

The product of its (nonzero) digits is 85050, while the sum is 42.

The square root of 19965705 is about 4468.3000123089. The cubic root of 19965705 is about 271.2865213059.

The spelling of 19965705 in words is "nineteen million, nine hundred sixty-five thousand, seven hundred five".