6501626881 has 4 divisors (see below), whose sum is σ = 6503164164. Its totient is φ = 6500089600.

The previous prime is 6501626861. The next prime is 6501626893. The reversal of 6501626881 is 1886261056.

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 2885408656 + 3616218225 = 53716^2 + 60135^2 .

It is a cyclic number.

It is not a de Polignac number, because 6501626881 - 2⁵ = 6501626849 is a prime.

It is a super-2 number, since 2×6501626881² = 84542304199483576322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6501626801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 762280 + ... + 770761.

It is an arithmetic number, because the mean of its divisors is an integer number (1625791041).

Almost surely, 2^6501626881 is an apocalyptic number.

It is an amenable number.

6501626881 is a deficient number, since it is larger than the sum of its proper divisors (1537283).

6501626881 is a wasteful number, since it uses less digits than its factorization.

6501626881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1537282.

The product of its (nonzero) digits is 138240, while the sum is 43.

The square root of 6501626881 is about 80632.6663393937. Note that the first 3 decimals coincide. The cubic root of 6501626881 is about 1866.4112667404.

The spelling of 6501626881 in words is "six billion, five hundred one million, six hundred twenty-six thousand, eight hundred eighty-one".