20212774517 has 4 divisors (see below), whose sum is σ = 21767603340. Its totient is φ = 18657945696.

The previous prime is 20212774507. The next prime is 20212774537. The reversal of 20212774517 is 71547721202.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71547721202 = 2 ⋅35773860601.

It can be written as a sum of positive squares in 2 ways, for example, as 2903162161 + 17309612356 = 53881^2 + 131566^2 .

It is not a de Polignac number, because 20212774517 - 2¹² = 20212770421 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 (20212774507) 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 3 ways as a sum of consecutive naturals, for example, 777414392 + ... + 777414417.

It is an arithmetic number, because the mean of its divisors is an integer number (5441900835).

Almost surely, 2^20212774517 is an apocalyptic number.

It is an amenable number.

20212774517 is a deficient number, since it is larger than the sum of its proper divisors (1554828823).

20212774517 is a wasteful number, since it uses less digits than its factorization.

20212774517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1554828822.

The product of its (nonzero) digits is 54880, while the sum is 38.

The spelling of 20212774517 in words is "twenty billion, two hundred twelve million, seven hundred seventy-four thousand, five hundred seventeen".