18400419 has 8 divisors (see below), whose sum is σ = 27259920. Its totient is φ = 12266928.

The previous prime is 18400397. The next prime is 18400423. The reversal of 18400419 is 91400481.

It is not a de Polignac number, because 18400419 - 2⁵ = 18400387 is a prime.

It is a super-2 number, since 2×18400419² = 677150838751122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 681497 = 18400419 / (1 + 8 + 4 + 0 + 0 + 4 + 1 + 9).

It is a junction number, because it is equal to n+sod(n) for n = 18400392 and 18400401.

It is not an unprimeable number, because it can be changed into a prime (18400439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 340722 + ... + 340775.

It is an arithmetic number, because the mean of its divisors is an integer number (3407490).

Almost surely, 2^18400419 is an apocalyptic number.

18400419 is a deficient number, since it is larger than the sum of its proper divisors (8859501).

18400419 is an equidigital number, since it uses as much as digits as its factorization.

18400419 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681506 (or 681500 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 18400419 is about 4289.5709575667. The cubic root of 18400419 is about 264.0032282663.

The spelling of 18400419 in words is "eighteen million, four hundred thousand, four hundred nineteen".