6545210661 has 12 divisors (see below), whose sum is σ = 10313665440. Its totient is φ = 3966794280.

The previous prime is 6545210627. The next prime is 6545210663. The reversal of 6545210661 is 1660125456.

6545210661 is a `hidden beast` number, since 6 + 545 + 2 + 106 + 6 + 1 = 666.

It is not a de Polignac number, because 6545210661 - 2¹⁷ = 6545079589 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6545210663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33056521 + ... + 33056718.

It is an arithmetic number, because the mean of its divisors is an integer number (859472120).

Almost surely, 2^6545210661 is an apocalyptic number.

It is an amenable number.

6545210661 is a deficient number, since it is larger than the sum of its proper divisors (3768454779).

6545210661 is a wasteful number, since it uses less digits than its factorization.

6545210661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66113256 (or 66113253 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The square root of 6545210661 is about 80902.4762352797. The cubic root of 6545210661 is about 1870.5724901258.

The spelling of 6545210661 in words is "six billion, five hundred forty-five million, two hundred ten thousand, six hundred sixty-one".