81625206389760 has 396 divisors, whose sum is σ = 310878414015624. Its totient is φ = 19787927470080.

The previous prime is 81625206389693. The next prime is 81625206389761. The reversal of 81625206389760 is 6798360252618.

It is a happy number.

81625206389760 is a `hidden beast` number, since 8 + 1 + 6 + 2 + 520 + 6 + 38 + 9 + 76 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (396).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81625206389761) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1744074 + ... + 12895433.

Almost surely, 2^{81625206389760} is an apocalyptic number.

81625206389760 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 81625206389760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (155439207007812).

81625206389760 is an abundant number, since it is smaller than the sum of its proper divisors (229253207625864).

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

81625206389760 is a wasteful number, since it uses less digits than its factorization.

81625206389760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14639560 (or 14639528 counting only the distinct ones).

The product of its (nonzero) digits is 52254720, while the sum is 63.

The spelling of 81625206389760 in words is "eighty-one trillion, six hundred twenty-five billion, two hundred six million, three hundred eighty-nine thousand, seven hundred sixty".