19665965 has 8 divisors (see below), whose sum is σ = 25744608. Its totient is φ = 14302480.

The previous prime is 19665949. The next prime is 19665967. The reversal of 19665965 is 56956691.

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

It is not a de Polignac number, because 19665965 - 2⁴ = 19665949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19665967) 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, 178727 + ... + 178836.

It is an arithmetic number, because the mean of its divisors is an integer number (3218076).

Almost surely, 2^19665965 is an apocalyptic number.

It is an amenable number.

19665965 is a deficient number, since it is larger than the sum of its proper divisors (6078643).

19665965 is a wasteful number, since it uses less digits than its factorization.

19665965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 357579.

The product of its digits is 437400, while the sum is 47.

The square root of 19665965 is about 4434.6324537666. The cubic root of 19665965 is about 269.9220854285.

The spelling of 19665965 in words is "nineteen million, six hundred sixty-five thousand, nine hundred sixty-five".