6421537394 has 8 divisors (see below), whose sum is σ = 10051102080. Its totient is φ = 3071170036.

The previous prime is 6421537393. The next prime is 6421537427. The reversal of 6421537394 is 4937351246.

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

It is a super-2 number, since 2×6421537394² = 82472285005080622472, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6421537393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69799274 + ... + 69799365.

It is an arithmetic number, because the mean of its divisors is an integer number (1256387760).

Almost surely, 2^6421537394 is an apocalyptic number.

6421537394 is a deficient number, since it is larger than the sum of its proper divisors (3629564686).

6421537394 is a wasteful number, since it uses less digits than its factorization.

6421537394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139598664.

The product of its digits is 544320, while the sum is 44.

The square root of 6421537394 is about 80134.4956557412. The cubic root of 6421537394 is about 1858.7158625899.

The spelling of 6421537394 in words is "six billion, four hundred twenty-one million, five hundred thirty-seven thousand, three hundred ninety-four".