2403664021 has 4 divisors (see below), whose sum is σ = 2622178944. Its totient is φ = 2185149100.

The previous prime is 2403664001. The next prime is 2403664031. The reversal of 2403664021 is 1204663042.

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 2403664021 - 2¹⁵ = 2403631253 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2403664001) 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, 109257445 + ... + 109257466.

It is an arithmetic number, because the mean of its divisors is an integer number (655544736).

Almost surely, 2^2403664021 is an apocalyptic number.

It is an amenable number.

2403664021 is a deficient number, since it is larger than the sum of its proper divisors (218514923).

2403664021 is a wasteful number, since it uses less digits than its factorization.

2403664021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 218514922.

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 2403664021 is about 49027.1763514890. The cubic root of 2403664021 is about 1339.5468916162.

The spelling of 2403664021 in words is "two billion, four hundred three million, six hundred sixty-four thousand, twenty-one".