81422784 has 42 divisors (see below), whose sum is σ = 233385360. Its totient is φ = 27140736.

The previous prime is 81422777. The next prime is 81422791. The reversal of 81422784 is 48722418.

It is an interprime number because it is at equal distance from previous prime (81422777) and next prime (81422791).

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 5 ways as a sum of consecutive naturals, for example, 70104 + ... + 71255.

Almost surely, 2^81422784 is an apocalyptic number.

It is an amenable number.

81422784 is an abundant number, since it is smaller than the sum of its proper divisors (151962576).

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

81422784 is a wasteful number, since it uses less digits than its factorization.

81422784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141377 (or 141364 counting only the distinct ones).

The product of its digits is 28672, while the sum is 36.

The square root of 81422784 is about 9023.4574304975. The cubic root of 81422784 is about 433.4263553093.

The spelling of 81422784 in words is "eighty-one million, four hundred twenty-two thousand, seven hundred eighty-four".