18620409 has 16 divisors (see below), whose sum is σ = 26008704. Its totient is φ = 11827200.

The previous prime is 18620387. The next prime is 18620417. The reversal of 18620409 is 90402681.

It is not a de Polignac number, because 18620409 - 2⁹ = 18619897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18620489) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28729 + ... + 29369.

It is an arithmetic number, because the mean of its divisors is an integer number (1625544).

Almost surely, 2^18620409 is an apocalyptic number.

It is an amenable number.

18620409 is a deficient number, since it is larger than the sum of its proper divisors (7388295).

18620409 is a wasteful number, since it uses less digits than its factorization.

18620409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1088.

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

The square root of 18620409 is about 4315.1371936475. The cubic root of 18620409 is about 265.0511779642.

The spelling of 18620409 in words is "eighteen million, six hundred twenty thousand, four hundred nine".