81242394 has 32 divisors (see below), whose sum is σ = 173505024. Its totient is φ = 25299120.

The previous prime is 81242353. The next prime is 81242419. The reversal of 81242394 is 49324218.

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, 912 + ... + 12779.

It is an arithmetic number, because the mean of its divisors is an integer number (5422032).

Almost surely, 2^81242394 is an apocalyptic number.

81242394 is an abundant number, since it is smaller than the sum of its proper divisors (92262630).

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

81242394 is a wasteful number, since it uses less digits than its factorization.

81242394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13762.

The product of its digits is 13824, while the sum is 33.

The square root of 81242394 is about 9013.4562738164. The cubic root of 81242394 is about 433.1060371418.

The spelling of 81242394 in words is "eighty-one million, two hundred forty-two thousand, three hundred ninety-four".