661176001 has 4 divisors (see below), whose sum is σ = 661241812. Its totient is φ = 661110192.

The previous prime is 661175993. The next prime is 661176023. The reversal of 661176001 is 100671166.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 100671166 = 2 ⋅50335583.

It can be written as a sum of positive squares in 2 ways, for example, as 378263601 + 282912400 = 19449^2 + 16820^2 .

It is a cyclic number.

It is not a de Polignac number, because 661176001 - 2³ = 661175993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661176601) 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, 14346 + ... + 39091.

It is an arithmetic number, because the mean of its divisors is an integer number (165310453).

Almost surely, 2^661176001 is an apocalyptic number.

It is an amenable number.

661176001 is a deficient number, since it is larger than the sum of its proper divisors (65811).

661176001 is a wasteful number, since it uses less digits than its factorization.

661176001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65810.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 661176001 is about 25713.3428593017. The cubic root of 661176001 is about 871.1755812648.

The spelling of 661176001 in words is "six hundred sixty-one million, one hundred seventy-six thousand, one".