815417844640 has 192 divisors, whose sum is σ = 2293898600448. Its totient is φ = 268023628800.

The previous prime is 815417844629. The next prime is 815417844643. The reversal of 815417844640 is 46448714518.

It is a super-2 number, since 2×815417844640² (a number of 25 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (52) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (815417844643) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3605295 + ... + 3824785.

It is an arithmetic number, because the mean of its divisors is an integer number (11947388544).

Almost surely, 2^815417844640 is an apocalyptic number.

815417844640 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 815417844640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1146949300224).

815417844640 is an abundant number, since it is smaller than the sum of its proper divisors (1478480755808).

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

815417844640 is a wasteful number, since it uses less digits than its factorization.

815417844640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219651 (or 219643 counting only the distinct ones).

The product of its (nonzero) digits is 3440640, while the sum is 52.

The spelling of 815417844640 in words is "eight hundred fifteen billion, four hundred seventeen million, eight hundred forty-four thousand, six hundred forty".