6561511090 has 8 divisors (see below), whose sum is σ = 11810719980. Its totient is φ = 2624604432.

The previous prime is 6561511043. The next prime is 6561511109. The reversal of 6561511090 is 901151656.

It can be written as a sum of positive squares in 2 ways, for example, as 6336000801 + 225510289 = 79599^2 + 15017^2 .

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

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, 328075545 + ... + 328075564.

Almost surely, 2^6561511090 is an apocalyptic number.

6561511090 is a deficient number, since it is larger than the sum of its proper divisors (5249208890).

6561511090 is a wasteful number, since it uses less digits than its factorization.

6561511090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656151116.

The product of its (nonzero) digits is 8100, while the sum is 34.

The square root of 6561511090 is about 81003.1548151058. The cubic root of 6561511090 is about 1872.1240499117.

The spelling of 6561511090 in words is "six billion, five hundred sixty-one million, five hundred eleven thousand, ninety".