816806615772 has 192 divisors, whose sum is σ = 2225492527104. Its totient is φ = 228356997120.

The previous prime is 816806615767. The next prime is 816806615789. The reversal of 816806615772 is 277516608618.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 790712568 + ... + 790713600.

It is an arithmetic number, because the mean of its divisors is an integer number (11591106912).

Almost surely, 2^816806615772 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 816806615772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1112746263552).

816806615772 is an abundant number, since it is smaller than the sum of its proper divisors (1408685911332).

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

816806615772 is a wasteful number, since it uses less digits than its factorization.

816806615772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1988 (or 1986 counting only the distinct ones).

The product of its (nonzero) digits is 6773760, while the sum is 57.

The spelling of 816806615772 in words is "eight hundred sixteen billion, eight hundred six million, six hundred fifteen thousand, seven hundred seventy-two".