815845641600 has 384 divisors, whose sum is σ = 2958417792000. Its totient is φ = 195963494400.

The previous prime is 815845641593. The next prime is 815845641601. The reversal of 815845641600 is 6146548518.

It is a tau number, because it is divible by the number of its divisors (384).

It is a super-2 number, since 2×815845641600² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 815845641600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (815845641601) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11474961 + ... + 11545839.

It is an arithmetic number, because the mean of its divisors is an integer number (7704213000).

Almost surely, 2^815845641600 is an apocalyptic number.

815845641600 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 815845641600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1479208896000).

815845641600 is an abundant number, since it is smaller than the sum of its proper divisors (2142572150400).

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

815845641600 is a wasteful number, since it uses less digits than its factorization.

815845641600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71026 (or 71009 counting only the distinct ones).

The product of its (nonzero) digits is 921600, while the sum is 48.

The spelling of 815845641600 in words is "eight hundred fifteen billion, eight hundred forty-five million, six hundred forty-one thousand, six hundred".