61066220557 has 16 divisors (see below), whose sum is σ = 64981033920. Its totient is φ = 57187982592.

The previous prime is 61066220543. The next prime is 61066220569. The reversal of 61066220557 is 75502266016.

61066220557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-61066220557 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61066223557) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2798194 + ... + 2819932.

It is an arithmetic number, because the mean of its divisors is an integer number (4061314620).

Almost surely, 2^61066220557 is an apocalyptic number.

It is an amenable number.

61066220557 is a deficient number, since it is larger than the sum of its proper divisors (3914813363).

61066220557 is a wasteful number, since it uses less digits than its factorization.

61066220557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22572.

The product of its (nonzero) digits is 151200, while the sum is 40.

The spelling of 61066220557 in words is "sixty-one billion, sixty-six million, two hundred twenty thousand, five hundred fifty-seven".