66551065550 has 24 divisors (see below), whose sum is σ = 124986787536. Its totient is φ = 26361973440.

The previous prime is 66551065549. The next prime is 66551065583. The reversal of 66551065550 is 5556015566.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6456119 + ... + 6466418.

It is an arithmetic number, because the mean of its divisors is an integer number (5207782814).

Almost surely, 2^66551065550 is an apocalyptic number.

66551065550 is a deficient number, since it is larger than the sum of its proper divisors (58435721986).

66551065550 is a wasteful number, since it uses less digits than its factorization.

66551065550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12922652 (or 12922647 counting only the distinct ones).

The product of its (nonzero) digits is 675000, while the sum is 44.

The spelling of 66551065550 in words is "sixty-six billion, five hundred fifty-one million, sixty-five thousand, five hundred fifty".