2021705505 has 24 divisors (see below), whose sum is σ = 3563688960. Its totient is φ = 1059966240.

The previous prime is 2021705461. The next prime is 2021705509. The reversal of 2021705505 is 5055071202.

It is a happy number.

2021705505 is a `hidden beast` number, since 20 + 21 + 70 + 550 + 5 = 666.

It is not a de Polignac number, because 2021705505 - 2²⁰ = 2020656929 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2021705509) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 378081 + ... + 383390.

It is an arithmetic number, because the mean of its divisors is an integer number (148487040).

Almost surely, 2^2021705505 is an apocalyptic number.

It is an amenable number.

2021705505 is a deficient number, since it is larger than the sum of its proper divisors (1541983455).

2021705505 is a wasteful number, since it uses less digits than its factorization.

2021705505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 761541 (or 761538 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 27.

The square root of 2021705505 is about 44963.3795994029. The cubic root of 2021705505 is about 1264.4625305568.

Adding to 2021705505 its reverse (5055071202), we get a palindrome (7076776707).

The spelling of 2021705505 in words is "two billion, twenty-one million, seven hundred five thousand, five hundred five".