2151566673256 has 384 divisors, whose sum is σ = 5883138172800. Its totient is φ = 722996305920.

The previous prime is 2151566673251. The next prime is 2151566673281. The reversal of 2151566673256 is 6523766651512.

It is a junction number, because it is equal to n+sod(n) for n = 2151566673197 and 2151566673206.

It is not an unprimeable number, because it can be changed into a prime (2151566673251) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 77735836 + ... + 77763508.

It is an arithmetic number, because the mean of its divisors is an integer number (15320672325).

Almost surely, 2^{2151566673256} is an apocalyptic number.

2151566673256 is a gapful number since it is divisible by the number (26) 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 2151566673256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2941569086400).

2151566673256 is an abundant number, since it is smaller than the sum of its proper divisors (3731571499544).

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

2151566673256 is a wasteful number, since it uses less digits than its factorization.

2151566673256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27809 (or 27798 counting only the distinct ones).

The product of its digits is 13608000, while the sum is 55.

The spelling of 2151566673256 in words is "two trillion, one hundred fifty-one billion, five hundred sixty-six million, six hundred seventy-three thousand, two hundred fifty-six".