20657221607706 has 16 divisors (see below), whose sum is σ = 41316400849824. Its totient is φ = 6885414263504.

The previous prime is 20657221607699. The next prime is 20657221607707. The reversal of 20657221607706 is 60770612275602.

It is a happy number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20657221607707) 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 7 ways as a sum of consecutive naturals, for example, 81430905 + ... + 81684188.

It is an arithmetic number, because the mean of its divisors is an integer number (2582275053114).

Almost surely, 2^{20657221607706} is an apocalyptic number.

20657221607706 is an abundant number, since it is smaller than the sum of its proper divisors (20659179242118).

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

20657221607706 is a wasteful number, since it uses less digits than its factorization.

20657221607706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163136205.

The product of its (nonzero) digits is 2963520, while the sum is 51.

The spelling of 20657221607706 in words is "twenty trillion, six hundred fifty-seven billion, two hundred twenty-one million, six hundred seven thousand, seven hundred six".