8121247664 has 80 divisors (see below), whose sum is σ = 16395236352. Its totient is φ = 3894718464.

The previous prime is 8121247639. The next prime is 8121247679. The reversal of 8121247664 is 4667421218.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7861292 + ... + 7862324.

Almost surely, 2^8121247664 is an apocalyptic number.

It is an amenable number.

8121247664 is an abundant number, since it is smaller than the sum of its proper divisors (8273988688).

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

8121247664 is a wasteful number, since it uses less digits than its factorization.

8121247664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1294 (or 1288 counting only the distinct ones).

The product of its digits is 129024, while the sum is 41.

The square root of 8121247664 is about 90117.9652677534. The cubic root of 8121247664 is about 2010.0533523787.

The spelling of 8121247664 in words is "eight billion, one hundred twenty-one million, two hundred forty-seven thousand, six hundred sixty-four".