19681265 has 8 divisors (see below), whose sum is σ = 23716968. Its totient is φ = 15678720.

The previous prime is 19681253. The next prime is 19681267. The reversal of 19681265 is 56218691.

It can be written as a sum of positive squares in 4 ways, for example, as 776161 + 18905104 = 881^2 + 4348^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 19681265 - 2⁶ = 19681201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19681267) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6962 + ... + 9371.

It is an arithmetic number, because the mean of its divisors is an integer number (2964621).

Almost surely, 2^19681265 is an apocalyptic number.

It is an amenable number.

19681265 is a deficient number, since it is larger than the sum of its proper divisors (4035703).

19681265 is a wasteful number, since it uses less digits than its factorization.

19681265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16579.

The product of its digits is 25920, while the sum is 38.

The square root of 19681265 is about 4436.3571767837. The cubic root of 19681265 is about 269.9920665250.

The spelling of 19681265 in words is "nineteen million, six hundred eighty-one thousand, two hundred sixty-five".