601511661 has 24 divisors (see below), whose sum is σ = 880442784. Its totient is φ = 395685600.

The previous prime is 601511641. The next prime is 601511717. The reversal of 601511661 is 166115106.

601511661 is a `hidden beast` number, since 601 + 51 + 1 + 6 + 6 + 1 = 666.

It is not a de Polignac number, because 601511661 - 2⁶ = 601511597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (601511641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 314470 + ... + 316376.

It is an arithmetic number, because the mean of its divisors is an integer number (36685116).

Almost surely, 2^601511661 is an apocalyptic number.

It is an amenable number.

601511661 is a deficient number, since it is larger than the sum of its proper divisors (278931123).

601511661 is a wasteful number, since it uses less digits than its factorization.

601511661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2361 (or 2358 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 601511661 is about 24525.7346678953. The cubic root of 601511661 is about 844.1403958661.

Adding to 601511661 its reverse (166115106), we get a palindrome (767626767).

The spelling of 601511661 in words is "six hundred one million, five hundred eleven thousand, six hundred sixty-one".