6651561516 has 12 divisors (see below), whose sum is σ = 15520310232. Its totient is φ = 2217187168.

The previous prime is 6651561509. The next prime is 6651561523. The reversal of 6651561516 is 6151651566.

It is an interprime number because it is at equal distance from previous prime (6651561509) and next prime (6651561523).

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×6651561516² = 88486541202264436512, which contains 22 as substring.

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, 277148385 + ... + 277148408.

It is an arithmetic number, because the mean of its divisors is an integer number (1293359186).

Almost surely, 2^6651561516 is an apocalyptic number.

It is an amenable number.

6651561516 is an abundant number, since it is smaller than the sum of its proper divisors (8868748716).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6651561516 is a wasteful number, since it uses less digits than its factorization.

6651561516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554296800 (or 554296798 counting only the distinct ones).

The product of its digits is 162000, while the sum is 42.

The square root of 6651561516 is about 81557.1058584106. The cubic root of 6651561516 is about 1880.6495337486.

The spelling of 6651561516 in words is "six billion, six hundred fifty-one million, five hundred sixty-one thousand, five hundred sixteen".