20605555751 has 16 divisors (see below), whose sum is σ = 22871665440. Its totient is φ = 18406840320.

The previous prime is 20605555739. The next prime is 20605555769. The reversal of 20605555751 is 15755550602.

It is a de Polignac number, because none of the positive numbers 2^k-20605555751 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20605555699 and 20605555708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20605255751) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 168311 + ... + 263703.

It is an arithmetic number, because the mean of its divisors is an integer number (1429479090).

Almost surely, 2^20605555751 is an apocalyptic number.

20605555751 is a deficient number, since it is larger than the sum of its proper divisors (2266109689).

20605555751 is a wasteful number, since it uses less digits than its factorization.

20605555751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95746.

The product of its (nonzero) digits is 262500, while the sum is 41.

The spelling of 20605555751 in words is "twenty billion, six hundred five million, five hundred fifty-five thousand, seven hundred fifty-one".