20947652077 has 4 divisors (see below), whose sum is σ = 22851984096. Its totient is φ = 19043320060.

The previous prime is 20947652051. The next prime is 20947652129. The reversal of 20947652077 is 77025674902.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20947652077 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20947652077.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20947652177) 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, 952165993 + ... + 952166014.

It is an arithmetic number, because the mean of its divisors is an integer number (5712996024).

Almost surely, 2^20947652077 is an apocalyptic number.

It is an amenable number.

20947652077 is a deficient number, since it is larger than the sum of its proper divisors (1904332019).

20947652077 is a wasteful number, since it uses less digits than its factorization.

20947652077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1904332018.

The product of its (nonzero) digits is 1481760, while the sum is 49.

The spelling of 20947652077 in words is "twenty billion, nine hundred forty-seven million, six hundred fifty-two thousand, seventy-seven".