18631641 has 16 divisors (see below), whose sum is σ = 28544384. Its totient is φ = 10589184.

The previous prime is 18631637. The next prime is 18631649. The reversal of 18631641 is 14613681.

It is not a de Polignac number, because 18631641 - 2² = 18631637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18631599 and 18631608.

It is not an unprimeable number, because it can be changed into a prime (18631649) 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 in 15 ways as a sum of consecutive naturals, for example, 1755 + ... + 6351.

It is an arithmetic number, because the mean of its divisors is an integer number (1784024).

Almost surely, 2^18631641 is an apocalyptic number.

It is an amenable number.

18631641 is a deficient number, since it is larger than the sum of its proper divisors (9912743).

18631641 is a wasteful number, since it uses less digits than its factorization.

18631641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4800.

The product of its digits is 3456, while the sum is 30.

The square root of 18631641 is about 4316.4384624364. The cubic root of 18631641 is about 265.1044610122.

The spelling of 18631641 in words is "eighteen million, six hundred thirty-one thousand, six hundred forty-one".