6442420991 has 8 divisors (see below), whose sum is σ = 6800934000. Its totient is φ = 6085851840.

The previous prime is 6442420981. The next prime is 6442420993. The reversal of 6442420991 is 1990242446.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6442420991 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 (6442420993) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 479150 + ... + 492411.

It is an arithmetic number, because the mean of its divisors is an integer number (850116750).

Almost surely, 2^6442420991 is an apocalyptic number.

6442420991 is a deficient number, since it is larger than the sum of its proper divisors (358513009).

6442420991 is a wasteful number, since it uses less digits than its factorization.

6442420991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 971929.

The product of its (nonzero) digits is 124416, while the sum is 41.

The square root of 6442420991 is about 80264.6933028464. The cubic root of 6442420991 is about 1860.7286033451.

The spelling of 6442420991 in words is "six billion, four hundred forty-two million, four hundred twenty thousand, nine hundred ninety-one".