6466993681 has 16 divisors (see below), whose sum is σ = 7043120640. Its totient is φ = 5913112320.

The previous prime is 6466993661. The next prime is 6466993703. The reversal of 6466993681 is 1863996646.

6466993681 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 6466993681 - 2¹⁷ = 6466862609 is a prime.

It is a super-2 number, since 2×6466993681² = 83644014540187859522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6466993661) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 427200 + ... + 442078.

It is an arithmetic number, because the mean of its divisors is an integer number (440195040).

Almost surely, 2^6466993681 is an apocalyptic number.

It is an amenable number.

6466993681 is a deficient number, since it is larger than the sum of its proper divisors (576126959).

6466993681 is a wasteful number, since it uses less digits than its factorization.

6466993681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15624.

The product of its digits is 10077696, while the sum is 58.

The square root of 6466993681 is about 80417.6204634283. The cubic root of 6466993681 is about 1863.0913330137.

The spelling of 6466993681 in words is "six billion, four hundred sixty-six million, nine hundred ninety-three thousand, six hundred eighty-one".