81633474 has 64 divisors (see below), whose sum is σ = 197433600. Its totient is φ = 24852096.

The previous prime is 81633467. The next prime is 81633493. The reversal of 81633474 is 47433618.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 71742 + ... + 72870.

It is an arithmetic number, because the mean of its divisors is an integer number (3084900).

Almost surely, 2^81633474 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81633474, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98716800).

81633474 is an abundant number, since it is smaller than the sum of its proper divisors (115800126).

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

81633474 is a wasteful number, since it uses less digits than its factorization.

81633474 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1256 (or 1250 counting only the distinct ones).

The product of its digits is 48384, while the sum is 36.

The square root of 81633474 is about 9035.1244595744. The cubic root of 81633474 is about 433.7998787134.

The spelling of 81633474 in words is "eighty-one million, six hundred thirty-three thousand, four hundred seventy-four".