6451648777781 has 8 divisors (see below), whose sum is σ = 6453571891200. Its totient is φ = 6449725956240.

The previous prime is 6451648777751. The next prime is 6451648777793. The reversal of 6451648777781 is 1877778461546.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6451648777781 is a prime.

It is a super-2 number, since 2×6451648777781² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6451648777751) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48917516 + ... + 49049226.

It is an arithmetic number, because the mean of its divisors is an integer number (806696486400).

Almost surely, 2^{6451648777781} is an apocalyptic number.

It is an amenable number.

6451648777781 is a deficient number, since it is larger than the sum of its proper divisors (1923113419).

6451648777781 is a wasteful number, since it uses less digits than its factorization.

6451648777781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145939.

The product of its digits is 442552320, while the sum is 71.

The spelling of 6451648777781 in words is "six trillion, four hundred fifty-one billion, six hundred forty-eight million, seven hundred seventy-seven thousand, seven hundred eighty-one".