671778277283520 has 2016 divisors, whose sum is σ = 2670054516380160. Its totient is φ = 154614052454400.

The previous prime is 671778277283447. The next prime is 671778277283527. The reversal of 671778277283520 is 25382772877176.

671778277283520 is a `hidden beast` number, since 6 + 7 + 1 + 7 + 7 + 8 + 2 + 77 + 28 + 3 + 520 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (671778277283527) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 853593744567 + ... + 853593745353.

It is an arithmetic number, because the mean of its divisors is an integer number (1324431803760).

Almost surely, 2^{671778277283520} is an apocalyptic number.

671778277283520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 671778277283520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1335027258190080).

671778277283520 is an abundant number, since it is smaller than the sum of its proper divisors (1998276239096640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

671778277283520 is a wasteful number, since it uses less digits than its factorization.

671778277283520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1515 (or 1491 counting only the distinct ones).

The product of its (nonzero) digits is 774466560, while the sum is 72.

The spelling of 671778277283520 in words is "six hundred seventy-one trillion, seven hundred seventy-eight billion, two hundred seventy-seven million, two hundred eighty-three thousand, five hundred twenty".