20775679457 has 8 divisors (see below), whose sum is σ = 22444392936. Its totient is φ = 19117049472.

The previous prime is 20775679433. The next prime is 20775679493. The reversal of 20775679457 is 75497657702.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 3992217856 + 16783461601 = 63184^2 + 129551^2 .

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 20775679457 - 2²⁶ = 20708570593 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20775679396 and 20775679405.

It is not an unprimeable number, because it can be changed into a prime (20775679427) 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, 2516588 + ... + 2524829.

It is an arithmetic number, because the mean of its divisors is an integer number (2805549117).

Almost surely, 2^20775679457 is an apocalyptic number.

It is an amenable number.

20775679457 is a deficient number, since it is larger than the sum of its proper divisors (1668713479).

20775679457 is a wasteful number, since it uses less digits than its factorization.

20775679457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5041747.

The product of its (nonzero) digits is 25930800, while the sum is 59.

The spelling of 20775679457 in words is "twenty billion, seven hundred seventy-five million, six hundred seventy-nine thousand, four hundred fifty-seven".