815946649518 has 256 divisors, whose sum is σ = 2213728247808. Its totient is φ = 193617216000.

The previous prime is 815946649477. The next prime is 815946649541.

It is a happy number.

815946649518 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 348545028 + ... + 348547368.

It is an arithmetic number, because the mean of its divisors is an integer number (8647375968).

Almost surely, 2^815946649518 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 815946649518, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1106864123904).

815946649518 is an abundant number, since it is smaller than the sum of its proper divisors (1397781598290).

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

815946649518 is a wasteful number, since it uses less digits than its factorization.

815946649518 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2951.

The product of its digits is 74649600, while the sum is 66.

The spelling of 815946649518 in words is "eight hundred fifteen billion, nine hundred forty-six million, six hundred forty-nine thousand, five hundred eighteen".