81492480 has 240 divisors, whose sum is σ = 294918624. Its totient is φ = 21565440.

The previous prime is 81492469. The next prime is 81492491. The reversal of 81492480 is 8429418.

It is an interprime number because it is at equal distance from previous prime (81492469) and next prime (81492491).

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 622015 + ... + 622145.

Almost surely, 2^81492480 is an apocalyptic number.

81492480 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 81492480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147459312).

81492480 is an abundant number, since it is smaller than the sum of its proper divisors (213426144).

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

81492480 is an equidigital number, since it uses as much as digits as its factorization.

81492480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169 (or 141 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 81492480 is about 9027.3185387467. The cubic root of 81492480 is about 433.5499876504.

The spelling of 81492480 in words is "eighty-one million, four hundred ninety-two thousand, four hundred eighty".