819135744 has 108 divisors (see below), whose sum is σ = 2536146144. Its totient is φ = 234028032.

The previous prime is 819135727. The next prime is 819135749. The reversal of 819135744 is 447531918.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 819135696 and 819135705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (819135749) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 26749 + ... + 48515.

Almost surely, 2^819135744 is an apocalyptic number.

819135744 is a gapful number since it is divisible by the number (84) 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 819135744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1268073072).

819135744 is an abundant number, since it is smaller than the sum of its proper divisors (1717010400).

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

819135744 is a wasteful number, since it uses less digits than its factorization.

819135744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21800 (or 21779 counting only the distinct ones).

The product of its digits is 120960, while the sum is 42.

The square root of 819135744 is about 28620.5475838601. The cubic root of 819135744 is about 935.6612113067.

The spelling of 819135744 in words is "eight hundred nineteen million, one hundred thirty-five thousand, seven hundred forty-four".