6468787021 has 4 divisors (see below), whose sum is σ = 6469070652. Its totient is φ = 6468503392.

The previous prime is 6468786991. The next prime is 6468787027. The reversal of 6468787021 is 1207878646.

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 5469342025 + 999444996 = 73955^2 + 31614^2 .

It is a cyclic number.

It is not a de Polignac number, because 6468787021 - 2⁹ = 6468786509 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 (6468787027) 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, 104296 + ... + 154321.

It is an arithmetic number, because the mean of its divisors is an integer number (1617267663).

Almost surely, 2^6468787021 is an apocalyptic number.

It is an amenable number.

6468787021 is a deficient number, since it is larger than the sum of its proper divisors (283631).

6468787021 is a wasteful number, since it uses less digits than its factorization.

6468787021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283630.

The product of its (nonzero) digits is 903168, while the sum is 49.

The square root of 6468787021 is about 80428.7698588011. The cubic root of 6468787021 is about 1863.2635329354.

The spelling of 6468787021 in words is "six billion, four hundred sixty-eight million, seven hundred eighty-seven thousand, twenty-one".