2157785228466 has 144 divisors (see below), whose sum is σ = 5528327837760. Its totient is φ = 606368790720.

The previous prime is 2157785228437. The next prime is 2157785228491. The reversal of 2157785228466 is 6648225877512.

2157785228466 is a `hidden beast` number, since 2 + 1 + 5 + 77 + 85 + 2 + 28 + 466 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 26197500 + ... + 26279736.

It is an arithmetic number, because the mean of its divisors is an integer number (38391165540).

Almost surely, 2^{2157785228466} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2157785228466, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2764163918880).

2157785228466 is an abundant number, since it is smaller than the sum of its proper divisors (3370542609294).

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

2157785228466 is a wasteful number, since it uses less digits than its factorization.

2157785228466 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82749 (or 82739 counting only the distinct ones).

The product of its digits is 90316800, while the sum is 63.

The spelling of 2157785228466 in words is "two trillion, one hundred fifty-seven billion, seven hundred eighty-five million, two hundred twenty-eight thousand, four hundred sixty-six".