1000666537 has 4 divisors (see below), whose sum is σ = 1077640900. Its totient is φ = 923692176.

The previous prime is 1000666523. The next prime is 1000666549. The reversal of 1000666537 is 7356660001.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7356660001 = 8161 ⋅901441.

It can be written as a sum of positive squares in 2 ways, for example, as 75533481 + 925133056 = 8691^2 + 30416^2 .

It is a cyclic number.

It is not a de Polignac number, because 1000666537 - 2⁷ = 1000666409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1000666637) 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, 38487162 + ... + 38487187.

It is an arithmetic number, because the mean of its divisors is an integer number (269410225).

Almost surely, 2^1000666537 is an apocalyptic number.

It is an amenable number.

1000666537 is a deficient number, since it is larger than the sum of its proper divisors (76974363).

1000666537 is an equidigital number, since it uses as much as digits as its factorization.

1000666537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76974362.

The product of its (nonzero) digits is 22680, while the sum is 34.

The square root of 1000666537 is about 31633.3137214551. The cubic root of 1000666537 is about 1000.2221296548. Note that the first 3 decimals are identical.

The spelling of 1000666537 in words is "one billion, six hundred sixty-six thousand, five hundred thirty-seven".