81589901910 has 192 divisors, whose sum is σ = 220636555776. Its totient is φ = 19289064960.

The previous prime is 81589901891. The next prime is 81589901917. The reversal of 81589901910 is 1910998518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81589901917) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 25049002 + ... + 25052258.

It is an arithmetic number, because the mean of its divisors is an integer number (1149148728).

Almost surely, 2^81589901910 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81589901910, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110318277888).

81589901910 is an abundant number, since it is smaller than the sum of its proper divisors (139046653866).

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

81589901910 is a wasteful number, since it uses less digits than its factorization.

81589901910 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3459 (or 3448 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 51.

The spelling of 81589901910 in words is "eighty-one billion, five hundred eighty-nine million, nine hundred one thousand, nine hundred ten".