20778226657 has 8 divisors (see below), whose sum is σ = 21795148800. Its totient is φ = 19770764640.

The previous prime is 20778226649. The next prime is 20778226661. The reversal of 20778226657 is 75662287702.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 20778226657 - 2³ = 20778226649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20778226457) 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, 2360532 + ... + 2369317.

It is an arithmetic number, because the mean of its divisors is an integer number (2724393600).

Almost surely, 2^20778226657 is an apocalyptic number.

It is an amenable number.

20778226657 is a deficient number, since it is larger than the sum of its proper divisors (1016922143).

20778226657 is a wasteful number, since it uses less digits than its factorization.

20778226657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4730063.

The product of its (nonzero) digits is 3951360, while the sum is 52.

The spelling of 20778226657 in words is "twenty billion, seven hundred seventy-eight million, two hundred twenty-six thousand, six hundred fifty-seven".