66061645450 has 12 divisors (see below), whose sum is σ = 122874660630. Its totient is φ = 26424658160.

The previous prime is 66061645439. The next prime is 66061645483. The reversal of 66061645450 is 5454616066.

66061645450 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 46355381809 + 19706263641 = 215303^2 + 140379^2 .

It is a junction number, because it is equal to n+sod(n) for n = 66061645397 and 66061645406.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 660616405 + ... + 660616504.

Almost surely, 2^66061645450 is an apocalyptic number.

66061645450 is a deficient number, since it is larger than the sum of its proper divisors (56813015180).

66061645450 is a wasteful number, since it uses less digits than its factorization.

66061645450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1321232921 (or 1321232916 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 43.

The spelling of 66061645450 in words is "sixty-six billion, sixty-one million, six hundred forty-five thousand, four hundred fifty".