2165990625 has 120 divisors (see below), whose sum is σ = 4159108800. Its totient is φ = 1122660000.

The previous prime is 2165990581. The next prime is 2165990627. The reversal of 2165990625 is 5260995612.

It is a happy number.

2165990625 is a `hidden beast` number, since 2 + 16 + 5 + 9 + 9 + 0 + 625 = 666.

It is not a de Polignac number, because 2165990625 - 2¹⁴ = 2165974241 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (2165990627) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 10884276 + ... + 10884474.

It is an arithmetic number, because the mean of its divisors is an integer number (34659240).

Almost surely, 2^2165990625 is an apocalyptic number.

2165990625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2165990625 is a deficient number, since it is larger than the sum of its proper divisors (1993118175).

2165990625 is an frugal number, since it uses more digits than its factorization.

2165990625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279 (or 250 counting only the distinct ones).

The product of its (nonzero) digits is 291600, while the sum is 45.

The square root of 2165990625 is about 46540.2043936208. The cubic root of 2165990625 is about 1293.8547489226.

The spelling of 2165990625 in words is "two billion, one hundred sixty-five million, nine hundred ninety thousand, six hundred twenty-five".