6420107681 has 8 divisors (see below), whose sum is σ = 7320666024. Its totient is φ = 5577649920.

The previous prime is 6420107653. The next prime is 6420107689. The reversal of 6420107681 is 1867010246.

It can be written as a sum of positive squares in 4 ways, for example, as 1141358656 + 5278749025 = 33784^2 + 72655^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 6420107681 - 2¹⁰ = 6420106657 is a prime.

It is a super-2 number, since 2×6420107681² = 82435565271270395522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6420107689) 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 7 ways as a sum of consecutive naturals, for example, 14524910 + ... + 14525351.

It is an arithmetic number, because the mean of its divisors is an integer number (915083253).

Almost surely, 2^6420107681 is an apocalyptic number.

It is an amenable number.

6420107681 is a deficient number, since it is larger than the sum of its proper divisors (900558343).

6420107681 is a wasteful number, since it uses less digits than its factorization.

6420107681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29050291.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 6420107681 is about 80125.5744503589. The cubic root of 6420107681 is about 1858.5779087369.

The spelling of 6420107681 in words is "six billion, four hundred twenty million, one hundred seven thousand, six hundred eighty-one".