9915413021 has 4 divisors (see below), whose sum is σ = 9966788412. Its totient is φ = 9864037632.

The previous prime is 9915412943. The next prime is 9915413059. The reversal of 9915413021 is 1203145199.

It is a happy number.

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 1718102500 + 8197310521 = 41450^2 + 90539^2 .

It is a cyclic number.

It is not a de Polignac number, because 9915413021 - 2¹⁴ = 9915396637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9915413071) 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, 25687406 + ... + 25687791.

It is an arithmetic number, because the mean of its divisors is an integer number (2491697103).

Almost surely, 2^9915413021 is an apocalyptic number.

It is an amenable number.

9915413021 is a deficient number, since it is larger than the sum of its proper divisors (51375391).

9915413021 is a wasteful number, since it uses less digits than its factorization.

9915413021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51375390.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 9915413021 is about 99576.1669326551. The cubic root of 9915413021 is about 2148.3429107053.

The spelling of 9915413021 in words is "nine billion, nine hundred fifteen million, four hundred thirteen thousand, twenty-one".