20771476906 has 4 divisors (see below), whose sum is σ = 31157215362. Its totient is φ = 10385738452.

The previous prime is 20771476903. The next prime is 20771476931. The reversal of 20771476906 is 60967417702.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 20532310681 + 239166225 = 143291^2 + 15465^2 .

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 20771476906.

It is not an unprimeable number, because it can be changed into a prime (20771476903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5192869225 + ... + 5192869228.

Almost surely, 2^20771476906 is an apocalyptic number.

20771476906 is a deficient number, since it is larger than the sum of its proper divisors (10385738456).

20771476906 is a wasteful number, since it uses less digits than its factorization.

20771476906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10385738455.

The product of its (nonzero) digits is 889056, while the sum is 49.

The spelling of 20771476906 in words is "twenty billion, seven hundred seventy-one million, four hundred seventy-six thousand, nine hundred six".