61665606590 has 64 divisors (see below), whose sum is σ = 133585182720. Its totient is φ = 20037663360.

The previous prime is 61665606571. The next prime is 61665606593. The reversal of 61665606590 is 9560656616.

It is a super-2 number, since 2×61665606590² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61665606593) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 206 + ... + 351185.

It is an arithmetic number, because the mean of its divisors is an integer number (2087268480).

Almost surely, 2^61665606590 is an apocalyptic number.

61665606590 is an abundant number, since it is smaller than the sum of its proper divisors (71919576130).

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

61665606590 is a wasteful number, since it uses less digits than its factorization.

61665606590 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351537.

The product of its (nonzero) digits is 1749600, while the sum is 50.

The spelling of 61665606590 in words is "sixty-one billion, six hundred sixty-five million, six hundred six thousand, five hundred ninety".