6513929881 has 2 divisors, whose sum is σ = 6513929882. Its totient is φ = 6513929880.

The previous prime is 6513929879. The next prime is 6513929893. The reversal of 6513929881 is 1889293156.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3728201481 + 2785728400 = 61059^2 + 52780^2 .

It is a cyclic number.

It is not a de Polignac number, because 6513929881 - 2¹ = 6513929879 is a prime.

It is a super-2 number, since 2×6513929881² = 84862564989169348322, which contains 22 as substring.

Together with 6513929879, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (6513929381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3256964940 + 3256964941.

It is an arithmetic number, because the mean of its divisors is an integer number (3256964941).

Almost surely, 2^6513929881 is an apocalyptic number.

It is an amenable number.

6513929881 is a deficient number, since it is larger than the sum of its proper divisors (1).

6513929881 is an equidigital number, since it uses as much as digits as its factorization.

6513929881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 933120, while the sum is 52.

The square root of 6513929881 is about 80708.9207027327. The cubic root of 6513929881 is about 1867.5877922225.

The spelling of 6513929881 in words is "six billion, five hundred thirteen million, nine hundred twenty-nine thousand, eight hundred eighty-one".