2145216517 has 2 divisors, whose sum is σ = 2145216518. Its totient is φ = 2145216516.

The previous prime is 2145216503. The next prime is 2145216547. The reversal of 2145216517 is 7156125412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1526152356 + 619064161 = 39066^2 + 24881^2 .

It is a cyclic number.

It is not a de Polignac number, because 2145216517 - 2⁷ = 2145216389 is a prime.

It is a super-2 number, since 2×2145216517² = 9203907809619222578, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2145216547) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1072608258 + 1072608259.

It is an arithmetic number, because the mean of its divisors is an integer number (1072608259).

Almost surely, 2^2145216517 is an apocalyptic number.

It is an amenable number.

2145216517 is a deficient number, since it is larger than the sum of its proper divisors (1).

2145216517 is an equidigital number, since it uses as much as digits as its factorization.

2145216517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16800, while the sum is 34.

The square root of 2145216517 is about 46316.4821310945. The cubic root of 2145216517 is about 1289.7049817113.

The spelling of 2145216517 in words is "two billion, one hundred forty-five million, two hundred sixteen thousand, five hundred seventeen".