81894586 has 16 divisors (see below), whose sum is σ = 126080640. Its totient is φ = 39876480.

The previous prime is 81894581. The next prime is 81894587. The reversal of 81894586 is 68549818.

It is a super-2 number, since 2×81894586² = 13413446432222792, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81894581) 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, 17770 + ... + 21898.

It is an arithmetic number, because the mean of its divisors is an integer number (7880040).

Almost surely, 2^81894586 is an apocalyptic number.

81894586 is a deficient number, since it is larger than the sum of its proper divisors (44186054).

81894586 is a wasteful number, since it uses less digits than its factorization.

81894586 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4389.

The product of its digits is 552960, while the sum is 49.

The square root of 81894586 is about 9049.5627518682. The cubic root of 81894586 is about 434.2619024155.

The spelling of 81894586 in words is "eighty-one million, eight hundred ninety-four thousand, five hundred eighty-six".