19961705 has 4 divisors (see below), whose sum is σ = 23954052. Its totient is φ = 15969360.

The previous prime is 19961687. The next prime is 19961719. The reversal of 19961705 is 50716991.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8779369 + 11182336 = 2963^2 + 3344^2 .

It is a de Polignac number, because none of the positive numbers 2^k-19961705 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1996166 + ... + 1996175.

It is an arithmetic number, because the mean of its divisors is an integer number (5988513).

Almost surely, 2^19961705 is an apocalyptic number.

It is an amenable number.

19961705 is a deficient number, since it is larger than the sum of its proper divisors (3992347).

19961705 is an equidigital number, since it uses as much as digits as its factorization.

19961705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3992346.

The product of its (nonzero) digits is 17010, while the sum is 38.

The square root of 19961705 is about 4467.8523923693. The cubic root of 19961705 is about 271.2684032620.

The spelling of 19961705 in words is "nineteen million, nine hundred sixty-one thousand, seven hundred five".