66321022201920 has 168 divisors, whose sum is σ = 228134690683224. Its totient is φ = 17684209778688.

The previous prime is 66321022201879. The next prime is 66321022201937. The reversal of 66321022201920 is 2910222012366.

66321022201920 is a `hidden beast` number, since 6 + 632 + 1 + 0 + 2 + 2 + 2 + 0 + 19 + 2 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 3496122123264 + 62824900078656 = 1869792^2 + 7926216^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35837592 + ... + 37642728.

Almost surely, 2^{66321022201920} is an apocalyptic number.

66321022201920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66321022201920 is an abundant number, since it is smaller than the sum of its proper divisors (161813668481304).

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

66321022201920 is a wasteful number, since it uses less digits than its factorization.

66321022201920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1817917 (or 1817904 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The spelling of 66321022201920 in words is "sixty-six trillion, three hundred twenty-one billion, twenty-two million, two hundred one thousand, nine hundred twenty".