40218331 has 4 divisors (see below), whose sum is σ = 41605200. Its totient is φ = 38831464.

The previous prime is 40218313. The next prime is 40218359. The reversal of 40218331 is 13381204.

It is a semiprime because it is the product of two primes.

It is a de Polignac number, because none of the positive numbers 2^k-40218331 is a prime.

It is a super-2 number, since 2×40218331² = 3235028296851122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40218391) 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, 693391 + ... + 693448.

It is an arithmetic number, because the mean of its divisors is an integer number (10401300).

Almost surely, 2^40218331 is an apocalyptic number.

40218331 is a deficient number, since it is larger than the sum of its proper divisors (1386869).

40218331 is a wasteful number, since it uses less digits than its factorization.

40218331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1386868.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 40218331 is about 6341.7924122443. The cubic root of 40218331 is about 342.6162952441.

Adding to 40218331 its reverse (13381204), we get a palindrome (53599535).

The spelling of 40218331 in words is "forty million, two hundred eighteen thousand, three hundred thirty-one".