40213921 has 8 divisors (see below), whose sum is σ = 43916544. Its totient is φ = 36519120.

The previous prime is 40213897. The next prime is 40213933. The reversal of 40213921 is 12931204.

40213921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 40213921 - 2⁵ = 40213889 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40213892 and 40213901.

It is not an unprimeable number, because it can be changed into a prime (40213021) 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 in 7 ways as a sum of consecutive naturals, for example, 16071 + ... + 18403.

It is an arithmetic number, because the mean of its divisors is an integer number (5489568).

Almost surely, 2^40213921 is an apocalyptic number.

It is an amenable number.

40213921 is a deficient number, since it is larger than the sum of its proper divisors (3702623).

40213921 is a wasteful number, since it uses less digits than its factorization.

40213921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3911.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 40213921 is about 6341.4447092126. Note that the first 3 decimals coincide. The cubic root of 40213921 is about 342.6037719903.

The spelling of 40213921 in words is "forty million, two hundred thirteen thousand, nine hundred twenty-one".