16021858 has 4 divisors (see below), whose sum is σ = 24032790. Its totient is φ = 8010928.

The previous prime is 16021849. The next prime is 16021861. The reversal of 16021858 is 85812061.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 14645929 + 1375929 = 3827^2 + 1173^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4005463 + ... + 4005466.

Almost surely, 2^16021858 is an apocalyptic number.

16021858 is a deficient number, since it is larger than the sum of its proper divisors (8010932).

16021858 is an equidigital number, since it uses as much as digits as its factorization.

16021858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8010931.

The product of its (nonzero) digits is 3840, while the sum is 31.

The square root of 16021858 is about 4002.7313174881. The cubic root of 16021858 is about 252.0989050752.

The spelling of 16021858 in words is "sixteen million, twenty-one thousand, eight hundred fifty-eight".