19945165 has 16 divisors (see below), whose sum is σ = 25446960. Its totient is φ = 14955520.

The previous prime is 19945153. The next prime is 19945171. The reversal of 19945165 is 56154991.

It can be written as a sum of positive squares in 8 ways, for example, as 470596 + 19474569 = 686^2 + 4413^2 .

It is not a de Polignac number, because 19945165 - 2¹¹ = 19943117 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38931 + ... + 39439.

It is an arithmetic number, because the mean of its divisors is an integer number (1590435).

Almost surely, 2^19945165 is an apocalyptic number.

It is an amenable number.

19945165 is a deficient number, since it is larger than the sum of its proper divisors (5501795).

19945165 is a wasteful number, since it uses less digits than its factorization.

19945165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 992.

The product of its digits is 48600, while the sum is 40.

The square root of 19945165 is about 4466.0010076130. The cubic root of 19945165 is about 271.1934594435.

The spelling of 19945165 in words is "nineteen million, nine hundred forty-five thousand, one hundred sixty-five".