18201956 has 6 divisors (see below), whose sum is σ = 31853430. Its totient is φ = 9100976.

The previous prime is 18201941. The next prime is 18201959. The reversal of 18201956 is 65910281.

It can be written as a sum of positive squares in only one way, i.e., 17355556 + 846400 = 4166^2 + 920^2 .

It is a super-2 number, since 2×18201956² = 662622404451872, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18201959) by changing a digit.

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, 2275241 + ... + 2275248.

It is an arithmetic number, because the mean of its divisors is an integer number (5308905).

Almost surely, 2^18201956 is an apocalyptic number.

It is an amenable number.

18201956 is a deficient number, since it is larger than the sum of its proper divisors (13651474).

18201956 is a wasteful number, since it uses less digits than its factorization.

18201956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4550493 (or 4550491 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 18201956 is about 4266.3750421171. The cubic root of 18201956 is about 263.0506343256.

The spelling of 18201956 in words is "eighteen million, two hundred one thousand, nine hundred fifty-six".