409997621 has 8 divisors (see below), whose sum is σ = 462693600. Its totient is φ = 359872240.

The previous prime is 409997617. The next prime is 409997669. The reversal of 409997621 is 126799904.

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

It is a cyclic number.

It is not a de Polignac number, because 409997621 - 2² = 409997617 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (409997221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 642311 + ... + 642948.

It is an arithmetic number, because the mean of its divisors is an integer number (57836700).

Almost surely, 2^409997621 is an apocalyptic number.

It is an amenable number.

409997621 is a deficient number, since it is larger than the sum of its proper divisors (52695979).

409997621 is a wasteful number, since it uses less digits than its factorization.

409997621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1285299.

The product of its (nonzero) digits is 244944, while the sum is 47.

The square root of 409997621 is about 20248.3979860136. The cubic root of 409997621 is about 742.8944472725.

The spelling of 409997621 in words is "four hundred nine million, nine hundred ninety-seven thousand, six hundred twenty-one".