5621510665 has 4 divisors (see below), whose sum is σ = 6745812804. Its totient is φ = 4497208528.

The previous prime is 5621510659. The next prime is 5621510669. The reversal of 5621510665 is 5660151265.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3455911369 + 2165599296 = 58787^2 + 46536^2 .

It is a cyclic number.

It is not a de Polignac number, because 5621510665 - 2⁵ = 5621510633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5621510669) 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, 562151062 + ... + 562151071.

It is an arithmetic number, because the mean of its divisors is an integer number (1686453201).

Almost surely, 2^5621510665 is an apocalyptic number.

It is an amenable number.

5621510665 is a deficient number, since it is larger than the sum of its proper divisors (1124302139).

5621510665 is a wasteful number, since it uses less digits than its factorization.

5621510665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1124302138.

The product of its (nonzero) digits is 54000, while the sum is 37.

The square root of 5621510665 is about 74976.7341580040. The cubic root of 5621510665 is about 1778.0788371484.

The spelling of 5621510665 in words is "five billion, six hundred twenty-one million, five hundred ten thousand, six hundred sixty-five".