20764761005 has 4 divisors (see below), whose sum is σ = 24917713212. Its totient is φ = 16611808800.

The previous prime is 20764761001. The next prime is 20764761007. The reversal of 20764761005 is 50016746702.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2917404169 + 17847356836 = 54013^2 + 133594^2 .

It is not a de Polignac number, because 20764761005 - 2² = 20764761001 is a prime.

It is a super-2 number, since 2×20764761005² (a number of 21 digits) contains 22 as substring.

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 20764761005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20764761001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2076476096 + ... + 2076476105.

It is an arithmetic number, because the mean of its divisors is an integer number (6229428303).

Almost surely, 2^20764761005 is an apocalyptic number.

It is an amenable number.

20764761005 is a deficient number, since it is larger than the sum of its proper divisors (4152952207).

20764761005 is an equidigital number, since it uses as much as digits as its factorization.

20764761005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4152952206.

The product of its (nonzero) digits is 70560, while the sum is 38.

The spelling of 20764761005 in words is "twenty billion, seven hundred sixty-four million, seven hundred sixty-one thousand, five".