820795261500 has 768 divisors, whose sum is σ = 2880280166400. Its totient is φ = 201218688000.

The previous prime is 820795261499. The next prime is 820795261501. The reversal of 820795261500 is 5162597028.

820795261500 is a `hidden beast` number, since 8 + 2 + 0 + 79 + 526 + 1 + 50 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (820795261499) and next prime (820795261501).

It is a super-2 number, since 2×820795261500² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820795261501) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 2589259342 + ... + 2589259658.

It is an arithmetic number, because the mean of its divisors is an integer number (3750364800).

Almost surely, 2^820795261500 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 820795261500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1440140083200).

820795261500 is an abundant number, since it is smaller than the sum of its proper divisors (2059484904900).

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

820795261500 is a wasteful number, since it uses less digits than its factorization.

820795261500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 668 (or 650 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 45.

The spelling of 820795261500 in words is "eight hundred twenty billion, seven hundred ninety-five million, two hundred sixty-one thousand, five hundred".