8213219725 has 6 divisors (see below), whose sum is σ = 10184392490. Its totient is φ = 6570575760.

The previous prime is 8213219681. The next prime is 8213219747. The reversal of 8213219725 is 5279123128.

It can be written as a sum of positive squares in 3 ways, for example, as 156900676 + 8056319049 = 12526^2 + 89757^2 .

It is not a de Polignac number, because 8213219725 - 2⁹ = 8213219213 is a prime.

It is a super-2 number, since 2×8213219725² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 164264370 + ... + 164264419.

Almost surely, 2^8213219725 is an apocalyptic number.

It is an amenable number.

8213219725 is a deficient number, since it is larger than the sum of its proper divisors (1971172765).

8213219725 is a wasteful number, since it uses less digits than its factorization.

8213219725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328528799 (or 328528794 counting only the distinct ones).

The product of its digits is 60480, while the sum is 40.

The square root of 8213219725 is about 90626.8157059488. The cubic root of 8213219725 is about 2017.6127506216.

The spelling of 8213219725 in words is "eight billion, two hundred thirteen million, two hundred nineteen thousand, seven hundred twenty-five".