9994788421 has 4 divisors (see below), whose sum is σ = 9995329152. Its totient is φ = 9994247692.

The previous prime is 9994788403. The next prime is 9994788457. The reversal of 9994788421 is 1248874999.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 9994788421 - 2²⁷ = 9860570693 is a prime.

It is a pancake number, because a pancake can be divided into 9994788421 parts by 141384 straight cuts.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 9994788421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9994788821) 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, 241621 + ... + 279946.

It is an arithmetic number, because the mean of its divisors is an integer number (2498832288).

Almost surely, 2^9994788421 is an apocalyptic number.

It is an amenable number.

9994788421 is a deficient number, since it is larger than the sum of its proper divisors (540731).

9994788421 is a wasteful number, since it uses less digits than its factorization.

9994788421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540730.

The product of its digits is 10450944, while the sum is 61.

The square root of 9994788421 is about 99973.9387090456. The cubic root of 9994788421 is about 2154.0603581094.

The spelling of 9994788421 in words is "nine billion, nine hundred ninety-four million, seven hundred eighty-eight thousand, four hundred twenty-one".