18641645 has 16 divisors (see below), whose sum is σ = 24743232. Its totient is φ = 13368960.

The previous prime is 18641629. The next prime is 18641653. The reversal of 18641645 is 54614681.

It is not a de Polignac number, because 18641645 - 2⁴ = 18641629 is a prime.

It is a super-3 number, since 3×18641645³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1694 + ... + 6336.

It is an arithmetic number, because the mean of its divisors is an integer number (1546452).

Almost surely, 2^18641645 is an apocalyptic number.

It is an amenable number.

18641645 is a deficient number, since it is larger than the sum of its proper divisors (6101587).

18641645 is a wasteful number, since it uses less digits than its factorization.

18641645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4732.

The product of its digits is 23040, while the sum is 35.

The square root of 18641645 is about 4317.5971326653. The cubic root of 18641645 is about 265.1519005712.

The spelling of 18641645 in words is "eighteen million, six hundred forty-one thousand, six hundred forty-five".