81019296 has 36 divisors (see below), whose sum is σ = 230399442. Its totient is φ = 27006336.

The previous prime is 81019291. The next prime is 81019333. The reversal of 81019296 is 69291018.

It can be written as a sum of positive squares in only one way, i.e., 63680400 + 17338896 = 7980^2 + 4164^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a self number, because there is not a number n which added to its sum of digits gives 81019296.

It is not an unprimeable number, because it can be changed into a prime (81019291) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 140371 + ... + 140946.

Almost surely, 2^81019296 is an apocalyptic number.

It is an amenable number.

81019296 is an abundant number, since it is smaller than the sum of its proper divisors (149380146).

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

81019296 is a wasteful number, since it uses less digits than its factorization.

81019296 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281333 (or 281322 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 81019296 is about 9001.0719361640. The cubic root of 81019296 is about 432.7092259541.

The spelling of 81019296 in words is "eighty-one million, nineteen thousand, two hundred ninety-six".