1606216521 has 64 divisors (see below), whose sum is σ = 2709504000. Its totient is φ = 840990528.

The previous prime is 1606216517. The next prime is 1606216541. The reversal of 1606216521 is 1256126061.

It is not a de Polignac number, because 1606216521 - 2² = 1606216517 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1606216511) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2233600 + ... + 2234318.

It is an arithmetic number, because the mean of its divisors is an integer number (42336000).

Almost surely, 2^1606216521 is an apocalyptic number.

It is an amenable number.

1606216521 is a deficient number, since it is larger than the sum of its proper divisors (1103287479).

1606216521 is a wasteful number, since it uses less digits than its factorization.

1606216521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 923 (or 909 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 1606216521 is about 40077.6311799987. The cubic root of 1606216521 is about 1171.1199058591.

The spelling of 1606216521 in words is "one billion, six hundred six million, two hundred sixteen thousand, five hundred twenty-one".