81211464000 has 224 divisors, whose sum is σ = 297956630400. Its totient is φ = 21656332800.

The previous prime is 81211463999. The next prime is 81211464013. The reversal of 81211464000 is 46411218.

It is a happy number.

81211464000 is a `hidden beast` number, since 8 + 1 + 2 + 1 + 14 + 640 + 0 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28011 + ... + 403989.

Almost surely, 2^81211464000 is an apocalyptic number.

81211464000 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 81211464000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148978315200).

81211464000 is an abundant number, since it is smaller than the sum of its proper divisors (216745166400).

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

81211464000 is a wasteful number, since it uses less digits than its factorization.

81211464000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 376015 (or 375989 counting only the distinct ones).

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

Adding to 81211464000 its reverse (46411218), we get a palindrome (81257875218).

The spelling of 81211464000 in words is "eighty-one billion, two hundred eleven million, four hundred sixty-four thousand".