661126511 has 8 divisors (see below), whose sum is σ = 673630848. Its totient is φ = 648711000.

The previous prime is 661126469. The next prime is 661126519. The reversal of 661126511 is 115621166.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661126511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661126519) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7085 + ... + 37046.

It is an arithmetic number, because the mean of its divisors is an integer number (84203856).

Almost surely, 2^661126511 is an apocalyptic number.

661126511 is a deficient number, since it is larger than the sum of its proper divisors (12504337).

661126511 is a wasteful number, since it uses less digits than its factorization.

661126511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44413.

The product of its digits is 2160, while the sum is 29.

The square root of 661126511 is about 25712.3805004515. The cubic root of 661126511 is about 871.1538444629.

Adding to 661126511 its reverse (115621166), we get a palindrome (776747677).

The spelling of 661126511 in words is "six hundred sixty-one million, one hundred twenty-six thousand, five hundred eleven".