40198421 has 16 divisors (see below), whose sum is σ = 43997184. Its totient is φ = 36578304.

The previous prime is 40198397. The next prime is 40198447. The reversal of 40198421 is 12489104.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40198421 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40198481) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 92621 + ... + 93053.

It is an arithmetic number, because the mean of its divisors is an integer number (2749824).

Almost surely, 2^40198421 is an apocalyptic number.

It is an amenable number.

40198421 is a deficient number, since it is larger than the sum of its proper divisors (3798763).

40198421 is a wasteful number, since it uses less digits than its factorization.

40198421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 40198421 is about 6340.2224724374. Note that the first 3 decimals coincide. The cubic root of 40198421 is about 342.5597487537.

The spelling of 40198421 in words is "forty million, one hundred ninety-eight thousand, four hundred twenty-one".