81246471837440 has 1152 divisors, whose sum is σ = 260062442422272. Its totient is φ = 23611330068480.

The previous prime is 81246471837389. The next prime is 81246471837469. The reversal of 81246471837440 is 4473817464218.

It is a self number, because there is not a number n which added to its sum of digits gives 81246471837440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 10547376629 + ... + 10547384331.

It is an arithmetic number, because the mean of its divisors is an integer number (225748647936).

Almost surely, 2^{81246471837440} is an apocalyptic number.

81246471837440 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 81246471837440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130031221211136).

81246471837440 is an abundant number, since it is smaller than the sum of its proper divisors (178815970584832).

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

81246471837440 is a wasteful number, since it uses less digits than its factorization.

81246471837440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7925 (or 7911 counting only the distinct ones).

The product of its (nonzero) digits is 28901376, while the sum is 59.

The spelling of 81246471837440 in words is "eighty-one trillion, two hundred forty-six billion, four hundred seventy-one million, eight hundred thirty-seven thousand, four hundred forty".