40198381 has 2 divisors, whose sum is σ = 40198382. Its totient is φ = 40198380.

The previous prime is 40198373. The next prime is 40198393. The reversal of 40198381 is 18389104.

It is a happy number.

40198381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39312900 + 885481 = 6270^2 + 941^2 .

It is a cyclic number.

It is not a de Polignac number, because 40198381 - 2³ = 40198373 is a prime.

It is a super-2 number, since 2×40198381² = 3231819670042322, which contains 22 as substring.

It is equal to p_2444992 and since 40198381 and 2444992 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40198481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20099190 + 20099191.

It is an arithmetic number, because the mean of its divisors is an integer number (20099191).

Almost surely, 2^40198381 is an apocalyptic number.

It is an amenable number.

40198381 is a deficient number, since it is larger than the sum of its proper divisors (1).

40198381 is an equidigital number, since it uses as much as digits as its factorization.

40198381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 40198381 is about 6340.2193179732. The cubic root of 40198381 is about 342.5596351307.

The spelling of 40198381 in words is "forty million, one hundred ninety-eight thousand, three hundred eighty-one".