9965997215 has 4 divisors (see below), whose sum is σ = 11959196664. Its totient is φ = 7972797768.

The previous prime is 9965997169. The next prime is 9965997241. The reversal of 9965997215 is 5127995699.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 9965997215 - 2²⁴ = 9949219999 is a prime.

It is a super-2 number, since 2×9965997215² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 996599717 + ... + 996599726.

It is an arithmetic number, because the mean of its divisors is an integer number (2989799166).

Almost surely, 2^9965997215 is an apocalyptic number.

9965997215 is a deficient number, since it is larger than the sum of its proper divisors (1993199449).

9965997215 is a wasteful number, since it uses less digits than its factorization.

9965997215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1993199448.

The product of its digits is 13778100, while the sum is 62.

The square root of 9965997215 is about 99829.8413050927. The cubic root of 9965997215 is about 2151.9900244346.

The spelling of 9965997215 in words is "nine billion, nine hundred sixty-five million, nine hundred ninety-seven thousand, two hundred fifteen".