81913248 has 96 divisors (see below), whose sum is σ = 241315200. Its totient is φ = 27030528.

The previous prime is 81913231. The next prime is 81913277. The reversal of 81913248 is 84231918.

It is a tau number, because it is divible by the number of its divisors (96).

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

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 97213 + ... + 98051.

It is an arithmetic number, because the mean of its divisors is an integer number (2513700).

Almost surely, 2^81913248 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 81913248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120657600).

81913248 is an abundant number, since it is smaller than the sum of its proper divisors (159401952).

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

81913248 is a wasteful number, since it uses less digits than its factorization.

81913248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 971 (or 957 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 81913248 is about 9050.5937926746. The cubic root of 81913248 is about 434.2948861999.

The spelling of 81913248 in words is "eighty-one million, nine hundred thirteen thousand, two hundred forty-eight".