81154560 has 80 divisors (see below), whose sum is σ = 259465536. Its totient is φ = 21639168.

The previous prime is 81154547. The next prime is 81154573. The reversal of 81154560 is 6545118.

It is an interprime number because it is at equal distance from previous prime (81154547) and next prime (81154573).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2397 + ... + 12963.

Almost surely, 2^81154560 is an apocalyptic number.

81154560 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 81154560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129732768).

81154560 is an abundant number, since it is smaller than the sum of its proper divisors (178310976).

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

81154560 is a wasteful number, since it uses less digits than its factorization.

81154560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10593 (or 10577 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 30.

The square root of 81154560 is about 9008.5825744120. The cubic root of 81154560 is about 432.9498988198.

Adding to 81154560 its reverse (6545118), we get a palindrome (87699678).

The spelling of 81154560 in words is "eighty-one million, one hundred fifty-four thousand, five hundred sixty".