1666246069 has 4 divisors (see below), whose sum is σ = 1723702860. Its totient is φ = 1608789280.

The previous prime is 1666246061. The next prime is 1666246129. The reversal of 1666246069 is 9606426661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1433531044 + 232715025 = 37862^2 + 15255^2 .

It is a cyclic number.

It is not a de Polignac number, because 1666246069 - 2³ = 1666246061 is a prime.

It is a super-2 number, since 2×1666246069² = 5552751924915905522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666246061) 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, 28728352 + ... + 28728409.

It is an arithmetic number, because the mean of its divisors is an integer number (430925715).

Almost surely, 2^1666246069 is an apocalyptic number.

It is an amenable number.

1666246069 is a deficient number, since it is larger than the sum of its proper divisors (57456791).

1666246069 is an equidigital number, since it uses as much as digits as its factorization.

1666246069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57456790.

The product of its (nonzero) digits is 559872, while the sum is 46.

The square root of 1666246069 is about 40819.6774730031. The cubic root of 1666246069 is about 1185.5313583709.

The spelling of 1666246069 in words is "one billion, six hundred sixty-six million, two hundred forty-six thousand, sixty-nine".