18648261 has 6 divisors (see below), whose sum is σ = 26936390. Its totient is φ = 12432168.

The previous prime is 18648241. The next prime is 18648263. The reversal of 18648261 is 16284681.

18648261 is a `hidden beast` number, since 1 + 8 + 648 + 2 + 6 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 11390625 + 7257636 = 3375^2 + 2694^2 .

It is not a de Polignac number, because 18648261 - 2⁵ = 18648229 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18648263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1036006 + ... + 1036023.

Almost surely, 2^18648261 is an apocalyptic number.

It is an amenable number.

18648261 is a deficient number, since it is larger than the sum of its proper divisors (8288129).

18648261 is a wasteful number, since it uses less digits than its factorization.

18648261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2072035 (or 2072032 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 18648261 is about 4318.3632315960. The cubic root of 18648261 is about 265.1832647111.

The spelling of 18648261 in words is "eighteen million, six hundred forty-eight thousand, two hundred sixty-one".