20661222766 has 8 divisors (see below), whose sum is σ = 30995028864. Its totient is φ = 10329546480.

The previous prime is 20661222761. The next prime is 20661222773. The reversal of 20661222766 is 66722216602.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×20661222766² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20661222761) 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 3 ways as a sum of consecutive naturals, for example, 507975 + ... + 547138.

It is an arithmetic number, because the mean of its divisors is an integer number (3874378608).

Almost surely, 2^20661222766 is an apocalyptic number.

20661222766 is a deficient number, since it is larger than the sum of its proper divisors (10333806098).

20661222766 is a wasteful number, since it uses less digits than its factorization.

20661222766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1064906.

The product of its (nonzero) digits is 145152, while the sum is 40.

The spelling of 20661222766 in words is "twenty billion, six hundred sixty-one million, two hundred twenty-two thousand, seven hundred sixty-six".