81152403840 has 384 divisors, whose sum is σ = 284617307520. Its totient is φ = 21304442880.

The previous prime is 81152403823. The next prime is 81152403851. The reversal of 81152403840 is 4830425118.

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

It is a super-3 number, since 3×81152403840³ (a number of 34 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 81152403795 and 81152403804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 188288425 + ... + 188288855.

It is an arithmetic number, because the mean of its divisors is an integer number (741190905).

Almost surely, 2^81152403840 is an apocalyptic number.

81152403840 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 81152403840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142308653760).

81152403840 is an abundant number, since it is smaller than the sum of its proper divisors (203464903680).

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

81152403840 is a wasteful number, since it uses less digits than its factorization.

81152403840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 890 (or 875 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

Adding to 81152403840 its reverse (4830425118), we get a palindrome (85982828958).

The spelling of 81152403840 in words is "eighty-one billion, one hundred fifty-two million, four hundred three thousand, eight hundred forty".