66406026020 has 24 divisors (see below), whose sum is σ = 143221646904. Its totient is φ = 25844507136.

The previous prime is 66406026017. The next prime is 66406026047. The reversal of 66406026020 is 2062060466.

It can be written as a sum of positive squares in 4 ways, for example, as 43353069796 + 23052956224 = 208214^2 + 151832^2 .

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 44868197 + ... + 44869676.

It is an arithmetic number, because the mean of its divisors is an integer number (5967568621).

Almost surely, 2^66406026020 is an apocalyptic number.

It is an amenable number.

66406026020 is an abundant number, since it is smaller than the sum of its proper divisors (76815620884).

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

66406026020 is a wasteful number, since it uses less digits than its factorization.

66406026020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89737919 (or 89737917 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 32.

Adding to 66406026020 its reverse (2062060466), we get a palindrome (68468086486).

The spelling of 66406026020 in words is "sixty-six billion, four hundred six million, twenty-six thousand, twenty".