20761876997 has 4 divisors (see below), whose sum is σ = 21477803820. Its totient is φ = 20045950176.

The previous prime is 20761876991. The next prime is 20761877033. The reversal of 20761876997 is 79967816702.

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 11141013601 + 9620863396 = 105551^2 + 98086^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20761876997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20761876991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 357963368 + ... + 357963425.

It is an arithmetic number, because the mean of its divisors is an integer number (5369450955).

Almost surely, 2^20761876997 is an apocalyptic number.

It is an amenable number.

20761876997 is a deficient number, since it is larger than the sum of its proper divisors (715926823).

20761876997 is an equidigital number, since it uses as much as digits as its factorization.

20761876997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 715926822.

The product of its (nonzero) digits is 16003008, while the sum is 62.

The spelling of 20761876997 in words is "twenty billion, seven hundred sixty-one million, eight hundred seventy-six thousand, nine hundred ninety-seven".