81453120 has 448 divisors, whose sum is σ = 337084416. Its totient is φ = 16220160.

The previous prime is 81453109. The next prime is 81453139. The reversal of 81453120 is 2135418.

It is a tau number, because it is divible by the number of its divisors (448).

It is a super-2 number, since 2×81453120² = 13269221515468800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2627505 + ... + 2627535.

Almost surely, 2^81453120 is an apocalyptic number.

81453120 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 81453120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (168542208).

81453120 is an abundant number, since it is smaller than the sum of its proper divisors (255631296).

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

81453120 is a wasteful number, since it uses less digits than its factorization.

81453120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98 (or 88 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 81453120 is about 9025.1382260883. The cubic root of 81453120 is about 433.4801764009.

Adding to 81453120 its reverse (2135418), we get a palindrome (83588538).

The spelling of 81453120 in words is "eighty-one million, four hundred fifty-three thousand, one hundred twenty".