81901858 has 16 divisors (see below), whose sum is σ = 128016000. Its totient is φ = 39250512.

The previous prime is 81901849. The next prime is 81901861. The reversal of 81901858 is 85810918.

It is a self number, because there is not a number n which added to its sum of digits gives 81901858.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2983 + ... + 13141.

It is an arithmetic number, because the mean of its divisors is an integer number (8001000).

Almost surely, 2^81901858 is an apocalyptic number.

81901858 is a deficient number, since it is larger than the sum of its proper divisors (46114142).

81901858 is a wasteful number, since it uses less digits than its factorization.

81901858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10329.

The product of its (nonzero) digits is 23040, while the sum is 40.

The square root of 81901858 is about 9049.9645303172. The cubic root of 81901858 is about 434.2747557645.

The spelling of 81901858 in words is "eighty-one million, nine hundred one thousand, eight hundred fifty-eight".