820117601772 has 96 divisors (see below), whose sum is σ = 2235366131712. Its totient is φ = 229143396096.

The previous prime is 820117601701. The next prime is 820117601783. The reversal of 820117601772 is 277106711028.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4703298 + ... + 4874550.

It is an arithmetic number, because the mean of its divisors is an integer number (23285063872).

Almost surely, 2^820117601772 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 820117601772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1117683065856).

820117601772 is an abundant number, since it is smaller than the sum of its proper divisors (1415248529940).

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

820117601772 is a wasteful number, since it uses less digits than its factorization.

820117601772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172527 (or 172525 counting only the distinct ones).

The product of its (nonzero) digits is 65856, while the sum is 42.

The spelling of 820117601772 in words is "eight hundred twenty billion, one hundred seventeen million, six hundred one thousand, seven hundred seventy-two".