20640044701 has 2 divisors, whose sum is σ = 20640044702. Its totient is φ = 20640044700.

The previous prime is 20640044693. The next prime is 20640044707. The reversal of 20640044701 is 10744004602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17214752025 + 3425292676 = 131205^2 + 58526^2 .

It is a cyclic number.

It is not a de Polignac number, because 20640044701 - 2³ = 20640044693 is a prime.

It is a super-2 number, since 2×20640044701² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20640044701.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20640044707) 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 as a sum of consecutive naturals, namely, 10320022350 + 10320022351.

It is an arithmetic number, because the mean of its divisors is an integer number (10320022351).

Almost surely, 2^20640044701 is an apocalyptic number.

It is an amenable number.

20640044701 is a deficient number, since it is larger than the sum of its proper divisors (1).

20640044701 is an equidigital number, since it uses as much as digits as its factorization.

20640044701 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 28.

The spelling of 20640044701 in words is "twenty billion, six hundred forty million, forty-four thousand, seven hundred one".