660975538 has 8 divisors (see below), whose sum is σ = 1049784732. Its totient is φ = 311047296.

The previous prime is 660975527. The next prime is 660975577. The reversal of 660975538 is 835579066.

It can be written as a sum of positive squares in 2 ways, for example, as 630361449 + 30614089 = 25107^2 + 5533^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-6 number, since 6×660975538⁶ (a number of 54 digits) contains 666666 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 660975491 and 660975500.

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, 9720195 + ... + 9720262.

Almost surely, 2^660975538 is an apocalyptic number.

660975538 is a deficient number, since it is larger than the sum of its proper divisors (388809194).

660975538 is a wasteful number, since it uses less digits than its factorization.

660975538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19440476.

The product of its (nonzero) digits is 1360800, while the sum is 49.

The square root of 660975538 is about 25709.4445291998. Note that the first 3 decimals coincide. The cubic root of 660975538 is about 871.0875279967.

The spelling of 660975538 in words is "six hundred sixty million, nine hundred seventy-five thousand, five hundred thirty-eight".