40821218 has 4 divisors (see below), whose sum is σ = 61231830. Its totient is φ = 20410608.

The previous prime is 40821217. The next prime is 40821223. The reversal of 40821218 is 81212804.

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

It can be written as a sum of positive squares in only one way, i.e., 39980329 + 840889 = 6323^2 + 917^2 .

It is not an unprimeable number, because it can be changed into a prime (40821217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10205303 + ... + 10205306.

Almost surely, 2^40821218 is an apocalyptic number.

40821218 is a deficient number, since it is larger than the sum of its proper divisors (20410612).

40821218 is a wasteful number, since it uses less digits than its factorization.

40821218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20410611.

The product of its (nonzero) digits is 1024, while the sum is 26.

The square root of 40821218 is about 6389.1484565629. The cubic root of 40821218 is about 344.3197911832.

The spelling of 40821218 in words is "forty million, eight hundred twenty-one thousand, two hundred eighteen".