6661542261 has 8 divisors (see below), whose sum is σ = 9689516064. Its totient is φ = 4037298320.

The previous prime is 6661542247. The next prime is 6661542289. The reversal of 6661542261 is 1622451666.

6661542261 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 6661542261 - 2¹⁸ = 6661280117 is a prime.

It is a super-2 number, since 2×6661542261² = 88752290590177984242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6661542061) 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, 100932426 + ... + 100932491.

It is an arithmetic number, because the mean of its divisors is an integer number (1211189508).

Almost surely, 2^6661542261 is an apocalyptic number.

It is an amenable number.

6661542261 is a deficient number, since it is larger than the sum of its proper divisors (3027973803).

6661542261 is a wasteful number, since it uses less digits than its factorization.

6661542261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201864931.

The product of its digits is 103680, while the sum is 39.

The square root of 6661542261 is about 81618.2716124276. The cubic root of 6661542261 is about 1881.5897091175.

The spelling of 6661542261 in words is "six billion, six hundred sixty-one million, five hundred forty-two thousand, two hundred sixty-one".