1665278272 has 28 divisors (see below), whose sum is σ = 3776614240. Its totient is φ = 713690496.

The previous prime is 1665278267. The next prime is 1665278273. The reversal of 1665278272 is 2728725661.

It is a tau number, because it is divible by the number of its divisors (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665278273) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1858122 + ... + 1859017.

It is an arithmetic number, because the mean of its divisors is an integer number (134879080).

Almost surely, 2^1665278272 is an apocalyptic number.

It is an amenable number.

1665278272 is an abundant number, since it is smaller than the sum of its proper divisors (2111335968).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1665278272 is an equidigital number, since it uses as much as digits as its factorization.

1665278272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3717158 (or 3717148 counting only the distinct ones).

The product of its digits is 564480, while the sum is 46.

The square root of 1665278272 is about 40807.8212111355. The cubic root of 1665278272 is about 1185.3017852560.

The spelling of 1665278272 in words is "one billion, six hundred sixty-five million, two hundred seventy-eight thousand, two hundred seventy-two".