81397458 has 24 divisors (see below), whose sum is σ = 176836608. Its totient is φ = 27059352.

The previous prime is 81397457. The next prime is 81397469. The reversal of 81397458 is 85479318.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81397457) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 991 + ... + 12797.

It is an arithmetic number, because the mean of its divisors is an integer number (7368192).

Almost surely, 2^81397458 is an apocalyptic number.

81397458 is an abundant number, since it is smaller than the sum of its proper divisors (95439150).

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

81397458 is a wasteful number, since it uses less digits than its factorization.

81397458 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12198 (or 12195 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 81397458 is about 9022.0539790006. The cubic root of 81397458 is about 433.3814125483.

The spelling of 81397458 in words is "eighty-one million, three hundred ninety-seven thousand, four hundred fifty-eight".