823011840 has 540 divisors, whose sum is σ = 3443031306. Its totient is φ = 188116992.

The previous prime is 823011811. The next prime is 823011841. The reversal of 823011840 is 48110328.

It can be written as a sum of positive squares in only one way, i.e., 740710656 + 82301184 = 27216^2 + 9072^2 .

It is a tau number, because it is divible by the number of its divisors (540).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (823011841) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 117573117 + ... + 117573123.

Almost surely, 2^823011840 is an apocalyptic number.

823011840 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 823011840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1721515653).

823011840 is an abundant number, since it is smaller than the sum of its proper divisors (2620019466).

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

823011840 is an frugal number, since it uses more digits than its factorization.

823011840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61 (or 17 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 823011840 is about 28688.1829330475. The cubic root of 823011840 is about 937.1347184925.

The spelling of 823011840 in words is "eight hundred twenty-three million, eleven thousand, eight hundred forty".