81325987470 has 768 divisors, whose sum is σ = 293439283200. Its totient is φ = 15833180160.

The previous prime is 81325987459. The next prime is 81325987471. The reversal of 81325987470 is 7478952318.

It is a happy number.

81325987470 is a `hidden beast` number, since 8 + 1 + 3 + 2 + 598 + 7 + 47 + 0 = 666.

It is a super-2 number, since 2×81325987470² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81325987471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 133979907 + ... + 133980513.

It is an arithmetic number, because the mean of its divisors is an integer number (382082400).

Almost surely, 2^81325987470 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81325987470, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146719641600).

81325987470 is an abundant number, since it is smaller than the sum of its proper divisors (212113295730).

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

81325987470 is a wasteful number, since it uses less digits than its factorization.

81325987470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 710 (or 697 counting only the distinct ones).

The product of its (nonzero) digits is 3386880, while the sum is 54.

The spelling of 81325987470 in words is "eighty-one billion, three hundred twenty-five million, nine hundred eighty-seven thousand, four hundred seventy".