533811856815666 has 576 divisors, whose sum is σ = 1397316601699200. Its totient is φ = 146275379712000.

The previous prime is 533811856815617. The next prime is 533811856815691. The reversal of 533811856815666 is 666518658118335.

It is a junction number, because it is equal to n+sod(n) for n = 533811856815594 and 533811856815603.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 254317224685 + ... + 254317226783.

It is an arithmetic number, because the mean of its divisors is an integer number (2425896877950).

Almost surely, 2^{533811856815666} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 533811856815666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (698658300849600).

533811856815666 is an abundant number, since it is smaller than the sum of its proper divisors (863504744883534).

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

533811856815666 is a wasteful number, since it uses less digits than its factorization.

533811856815666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3143 (or 3129 counting only the distinct ones).

The product of its digits is 746496000, while the sum is 72.

The spelling of 533811856815666 in words is "five hundred thirty-three trillion, eight hundred eleven billion, eight hundred fifty-six million, eight hundred fifteen thousand, six hundred sixty-six".