18721342 has 8 divisors (see below), whose sum is σ = 28132416. Its totient is φ = 9343872.

The previous prime is 18721331. The next prime is 18721343. The reversal of 18721342 is 24312781.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 18721342.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18721343) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6958 + ... + 9265.

It is an arithmetic number, because the mean of its divisors is an integer number (3516552).

Almost surely, 2^18721342 is an apocalyptic number.

18721342 is a deficient number, since it is larger than the sum of its proper divisors (9411074).

18721342 is a wasteful number, since it uses less digits than its factorization.

18721342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16802.

The product of its digits is 2688, while the sum is 28.

The square root of 18721342 is about 4326.8166127073. The cubic root of 18721342 is about 265.5292236385.

The spelling of 18721342 in words is "eighteen million, seven hundred twenty-one thousand, three hundred forty-two".