81258971904 has 360 divisors, whose sum is σ = 270804940560. Its totient is φ = 24020582400.

The previous prime is 81258971903. The next prime is 81258971987. The reversal of 81258971904 is 40917985218.

It is a happy number.

It is a super-2 number, since 2×81258971904² (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 not an unprimeable number, because it can be changed into a prime (81258971903) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 9347592 + ... + 9356280.

It is an arithmetic number, because the mean of its divisors is an integer number (752235946).

Almost surely, 2^81258971904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81258971904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135402470280).

81258971904 is an abundant number, since it is smaller than the sum of its proper divisors (189545968656).

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

81258971904 is a wasteful number, since it uses less digits than its factorization.

81258971904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8769 (or 8746 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 54.

The spelling of 81258971904 in words is "eighty-one billion, two hundred fifty-eight million, nine hundred seventy-one thousand, nine hundred four".