81863064 has 48 divisors (see below), whose sum is σ = 228870720. Its totient is φ = 26406720.

The previous prime is 81863063. The next prime is 81863069. The reversal of 81863064 is 46036818.

It is a happy number.

81863064 is a `hidden beast` number, since 8 + 18 + 630 + 6 + 4 = 666.

It is a super-2 number, since 2×81863064² = 13403122494936192, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81863063) 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, 16107 + ... + 20570.

It is an arithmetic number, because the mean of its divisors is an integer number (4768140).

Almost surely, 2^81863064 is an apocalyptic number.

It is an amenable number.

81863064 is an abundant number, since it is smaller than the sum of its proper divisors (147007656).

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

81863064 is a wasteful number, since it uses less digits than its factorization.

81863064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36720 (or 36713 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 81863064 is about 9047.8209531356. The cubic root of 81863064 is about 434.2061780954.

The spelling of 81863064 in words is "eighty-one million, eight hundred sixty-three thousand, sixty-four".