20654680381 has 4 divisors (see below), whose sum is σ = 20656929564. Its totient is φ = 20652431200.

The previous prime is 20654680339. The next prime is 20654680399. The reversal of 20654680381 is 18308645602.

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 9057328900 + 11597351481 = 95170^2 + 107691^2 .

It is a cyclic number.

It is not a de Polignac number, because 20654680381 - 2⁹ = 20654679869 is a prime.

It is a super-2 number, since 2×20654680381² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20654680181) 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, 1110760 + ... + 1129201.

It is an arithmetic number, because the mean of its divisors is an integer number (5164232391).

Almost surely, 2^20654680381 is an apocalyptic number.

It is an amenable number.

20654680381 is a deficient number, since it is larger than the sum of its proper divisors (2249183).

20654680381 is an equidigital number, since it uses as much as digits as its factorization.

20654680381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2249182.

The product of its (nonzero) digits is 276480, while the sum is 43.

The spelling of 20654680381 in words is "twenty billion, six hundred fifty-four million, six hundred eighty thousand, three hundred eighty-one".