18139450 has 24 divisors (see below), whose sum is σ = 38560032. Its totient is φ = 6219120.

The previous prime is 18139417. The next prime is 18139463. The reversal of 18139450 is 5493181.

18139450 = T₃₆₅ + T₃₆₆ + ... + T₅₃₉.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 25564 + ... + 26263.

It is an arithmetic number, because the mean of its divisors is an integer number (1606668).

Almost surely, 2^18139450 is an apocalyptic number.

18139450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18139450 is an abundant number, since it is smaller than the sum of its proper divisors (20420582).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18139450 is a wasteful number, since it uses less digits than its factorization.

18139450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51846 (or 51841 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 18139450 is about 4259.0433198079. The cubic root of 18139450 is about 262.7491813761.

The spelling of 18139450 in words is "eighteen million, one hundred thirty-nine thousand, four hundred fifty".