2106574721 has 4 divisors (see below), whose sum is σ = 2106687492. Its totient is φ = 2106461952.

The previous prime is 2106574709. The next prime is 2106574727. The reversal of 2106574721 is 1274756012.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1944369025 + 162205696 = 44095^2 + 12736^2 .

It is a cyclic number.

It is not a de Polignac number, because 2106574721 - 2¹⁰ = 2106573697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2106574727) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20936 + ... + 68201.

It is an arithmetic number, because the mean of its divisors is an integer number (526671873).

Almost surely, 2^2106574721 is an apocalyptic number.

It is an amenable number.

2106574721 is a deficient number, since it is larger than the sum of its proper divisors (112771).

2106574721 is an equidigital number, since it uses as much as digits as its factorization.

2106574721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112770.

The product of its (nonzero) digits is 23520, while the sum is 35.

The square root of 2106574721 is about 45897.4369763716. The cubic root of 2106574721 is about 1281.9141934614.

The spelling of 2106574721 in words is "two billion, one hundred six million, five hundred seventy-four thousand, seven hundred twenty-one".