9999400521 has 16 divisors (see below), whose sum is σ = 14547352320. Its totient is φ = 6059088720.

The previous prime is 9999400507. The next prime is 9999400529. The reversal of 9999400521 is 1250049999.

It is not a de Polignac number, because 9999400521 - 2⁶ = 9999400457 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9999400529) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 166890 + ... + 218748.

It is an arithmetic number, because the mean of its divisors is an integer number (909209520).

Almost surely, 2^9999400521 is an apocalyptic number.

It is an amenable number.

9999400521 is a deficient number, since it is larger than the sum of its proper divisors (4547951799).

9999400521 is a wasteful number, since it uses less digits than its factorization.

9999400521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57716.

The product of its (nonzero) digits is 262440, while the sum is 48.

The square root of 9999400521 is about 99997.0025600768. The cubic root of 9999400521 is about 2154.3916378931.

The spelling of 9999400521 in words is "nine billion, nine hundred ninety-nine million, four hundred thousand, five hundred twenty-one".