81207438 has 16 divisors (see below), whose sum is σ = 174908496. Its totient is φ = 24986880.

The previous prime is 81207433. The next prime is 81207439. The reversal of 81207438 is 83470218.

It is a junction number, because it is equal to n+sod(n) for n = 81207399 and 81207408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81207431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 520483 + ... + 520638.

It is an arithmetic number, because the mean of its divisors is an integer number (10931781).

Almost surely, 2^81207438 is an apocalyptic number.

81207438 is an abundant number, since it is smaller than the sum of its proper divisors (93701058).

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

81207438 is a wasteful number, since it uses less digits than its factorization.

81207438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1041139.

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 81207438 is about 9011.5169644184. The cubic root of 81207438 is about 433.0439110120.

The spelling of 81207438 in words is "eighty-one million, two hundred seven thousand, four hundred thirty-eight".