1001666042 has 12 divisors (see below), whose sum is σ = 1626966990. Its totient is φ = 462307248.

The previous prime is 1001666041. The next prime is 1001666051. The reversal of 1001666042 is 2406661001.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 380211001 + 621455041 = 19499^2 + 24929^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is not an unprimeable number, because it can be changed into a prime (1001666041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1481417 + ... + 1482092.

Almost surely, 2^1001666042 is an apocalyptic number.

1001666042 is a deficient number, since it is larger than the sum of its proper divisors (625300948).

1001666042 is a wasteful number, since it uses less digits than its factorization.

1001666042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2963537 (or 2963524 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 1001666042 is about 31649.1080759000. The cubic root of 1001666042 is about 1000.5550392078. Note that the first 3 decimals are identical.

The spelling of 1001666042 in words is "one billion, one million, six hundred sixty-six thousand, forty-two".