16404621 has 8 divisors (see below), whose sum is σ = 22181184. Its totient is φ = 10782240.

The previous prime is 16404599. The next prime is 16404623. The reversal of 16404621 is 12640461.

16404621 is digitally balanced in base 2 and base 4, because in such bases 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 16404621 - 2⁹ = 16404109 is a prime.

It is a super-2 number, since 2×16404621² = 538223180307282, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 16404591 and 16404600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16404623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38296 + ... + 38721.

It is an arithmetic number, because the mean of its divisors is an integer number (2772648).

Almost surely, 2^16404621 is an apocalyptic number.

It is an amenable number.

16404621 is a deficient number, since it is larger than the sum of its proper divisors (5776563).

16404621 is an equidigital number, since it uses as much as digits as its factorization.

16404621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77091.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 16404621 is about 4050.2618433874. The cubic root of 16404621 is about 254.0906789715.

The spelling of 16404621 in words is "sixteen million, four hundred four thousand, six hundred twenty-one".