815666043744 has 192 divisors, whose sum is σ = 2513560896000. Its totient is φ = 256619819520.

The previous prime is 815666043743. The next prime is 815666043757. The reversal of 815666043744 is 447340666518.

It is a super-2 number, since 2×815666043744² (a number of 25 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (815666043743) 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, 4323549 + ... + 4508259.

It is an arithmetic number, because the mean of its divisors is an integer number (13091463000).

Almost surely, 2^815666043744 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 815666043744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1256780448000).

815666043744 is an abundant number, since it is smaller than the sum of its proper divisors (1697894852256).

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

815666043744 is a wasteful number, since it uses less digits than its factorization.

815666043744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185018 (or 185004 counting only the distinct ones).

The product of its (nonzero) digits is 11612160, while the sum is 54.

The spelling of 815666043744 in words is "eight hundred fifteen billion, six hundred sixty-six million, forty-three thousand, seven hundred forty-four".