20554626761 has 4 divisors (see below), whose sum is σ = 21110157252. Its totient is φ = 19999096272.

The previous prime is 20554626737. The next prime is 20554626767. The reversal of 20554626761 is 16762645502.

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 19528385536 + 1026241225 = 139744^2 + 32035^2 .

It is a cyclic number.

It is not a de Polignac number, because 20554626761 - 2³⁴ = 3374757577 is a prime.

It is a super-2 number, since 2×20554626761² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20554626767) 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 in 3 ways as a sum of consecutive naturals, for example, 277765190 + ... + 277765263.

It is an arithmetic number, because the mean of its divisors is an integer number (5277539313).

Almost surely, 2^20554626761 is an apocalyptic number.

It is an amenable number.

20554626761 is a deficient number, since it is larger than the sum of its proper divisors (555530491).

20554626761 is an equidigital number, since it uses as much as digits as its factorization.

20554626761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555530490.

The product of its (nonzero) digits is 604800, while the sum is 44.

The spelling of 20554626761 in words is "twenty billion, five hundred fifty-four million, six hundred twenty-six thousand, seven hundred sixty-one".