40104821 has 4 divisors (see below), whose sum is σ = 40312812. Its totient is φ = 39896832.

The previous prime is 40104817. The next prime is 40104833. The reversal of 40104821 is 12840104.

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

It can be written as a sum of positive squares in 2 ways, for example, as 26635921 + 13468900 = 5161^2 + 3670^2 .

It is a cyclic number.

It is not a de Polignac number, because 40104821 - 2² = 40104817 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 40104793 and 40104802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40104811) 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, 103706 + ... + 104091.

It is an arithmetic number, because the mean of its divisors is an integer number (10078203).

Almost surely, 2^40104821 is an apocalyptic number.

It is an amenable number.

40104821 is a deficient number, since it is larger than the sum of its proper divisors (207991).

40104821 is a wasteful number, since it uses less digits than its factorization.

40104821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207990.

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 40104821 is about 6332.8367261441. The cubic root of 40104821 is about 342.2936644143.

Adding to 40104821 its reverse (12840104), we get a palindrome (52944925).

The spelling of 40104821 in words is "forty million, one hundred four thousand, eight hundred twenty-one".