20551426639 has 10 divisors (see below), whose sum is σ = 20976742480. Its totient is φ = 20131508124.

The previous prime is 20551426591. The next prime is 20551426717. The reversal of 20551426639 is 93662415502.

It is not a de Polignac number, because 20551426639 - 2²³ = 20543038031 is a prime.

It is a super-2 number, since 2×20551426639² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20551426595 and 20551426604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20551420639) 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 9 ways as a sum of consecutive naturals, for example, 161822194 + ... + 161822320.

It is an arithmetic number, because the mean of its divisors is an integer number (2097674248).

Almost surely, 2^20551426639 is an apocalyptic number.

20551426639 is a deficient number, since it is larger than the sum of its proper divisors (425315841).

20551426639 is an frugal number, since it uses more digits than its factorization.

20551426639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 587 (or 206 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 43.

The spelling of 20551426639 in words is "twenty billion, five hundred fifty-one million, four hundred twenty-six thousand, six hundred thirty-nine".