1665206216 has 16 divisors (see below), whose sum is σ = 3229926300. Its totient is φ = 803892544.

The previous prime is 1665206197. The next prime is 1665206297. The reversal of 1665206216 is 6126025661.

It can be written as a sum of positive squares in 2 ways, for example, as 1440506116 + 224700100 = 37954^2 + 14990^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3588575 + ... + 3589038.

Almost surely, 2^1665206216 is an apocalyptic number.

It is an amenable number.

1665206216 is a deficient number, since it is larger than the sum of its proper divisors (1564720084).

1665206216 is a wasteful number, since it uses less digits than its factorization.

1665206216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7177648 (or 7177644 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 1665206216 is about 40806.9383316122. The cubic root of 1665206216 is about 1185.2846891468.

The spelling of 1665206216 in words is "one billion, six hundred sixty-five million, two hundred six thousand, two hundred sixteen".